DJI Agras T100 OEM Screw (M25-HC00400040-050020-0003-N) (YC.WJ.LL000138)

DJI Agras T100 OEM Screw (M25-HC00400040-050020-0003-N) (YC.WJ.LL000138) — This is the DJI-specification fastener M25-HC00400040-050020-0003-N used in the aircraft frame of the DJI Agras T100. Fastener spec matters on a working aircraft: length, head form, thread, and coating are all encoded in the DJI designation, and the airframe was torqued and tested around exactly this hardware. A stripped, corroded, or missing one is how small problems become structural ones. DJI material number YC.WJ.LL000138. DJI Fastener M25-HC00400040-050020-0003-N | Airframe Hardware | Field-Ready OEM Replacement Component.

DJI Material Number (SKU): YC.WJ.LL000138 — this is the official DJI part number for this exact component. Match it to your parts diagram or your old part's label to confirm fitment before ordering.

🇺🇸 U.S.A. FIRST

Ares Acres LLC is a U.S.-based authorized DJI Agras reseller supporting American agricultural drone operators with genuine DJI Agras OEM replacement parts, accessories, and field-ready inventory.

FREE & FAST Shipping is included for all U.S. customers.

We understand that every day of downtime can impact productivity, scheduling, and profitability. That's why we focus on providing fast fulfillment, responsive customer support, and reliable access to the parts operators need most.

✅ DJI Agras T100 Compatibility Guarantee

• 🇺🇸 USA Compatibility Guarantee
• 👍🏻 Satisfaction Guarantee
• 💵 Money Back Guarantee
• 📦 Same Day Shipping & Tracking
• DJI material number YC.WJ.LL000138 — listed verbatim on the official DJI Agras T100 parts breakdown
• Supplier-listed fitment: DJI Agras T100
• Brand new condition — never installed, never flown

📦 Package Includes

• 1 × OEM Screw (M25-HC00400040-050020-0003-N) (YC.WJ.LL000138)
• OEM protective packaging

🔧 Component Overview

The DJI Agras T100 OEM Screw (M25-HC00400040-050020-0003-N) is the DJI-specification fastener used in the aircraft frame of the DJI Agras T100 — tying the airframe together under full payload and full power depends on hardware that stays torqued.

Tying the airframe together under full payload and full power is the job description for the aircraft frame, and this component is part of how it gets done. The T100 is a working machine — it earns its keep in fill-and-fly cycles, not hangar hours — and every component in the aircraft frame is sized, shaped, and specified around that duty.

Ignore a failing screw (m25-hc00400040-050020-0003-n) and the bill compounds: downtime in the middle of an application window, collateral wear on the parts around it, and jobs that slip to a competitor while the aircraft sits. Replacing it costs a part; not replacing it costs acres. That trade only runs one direction.

For professional farmers, aerial applicators, and commercial drone operators, this component is how the aircraft frame stays field-ready instead of becoming the reason the aircraft sits.

This is a working part on a working aircraft.

The T100 works brutally hard for its living, including:

• Tying the airframe together under full payload and full power
• Dawn-to-dusk spray campaigns during narrow application windows
• Repeated fill-fly-return cycles with minutes on the ground between loads
• Full-payload takeoffs from field edges, dozens of times per day
• Chemical exposure from fungicides, herbicides, insecticides, and foliar fertilizers
• Pressure-washer rinse-downs at the end of every spray day
• Vibration from eight propulsion motors running at working power
• Transport bouncing on trailers and truck beds between fields
• Temperature swings from cold morning starts to full-sun afternoons

What attacks this component in the field:

• Vibration constantly working against preload
• Torque cycles from repeated maintenance disassembly
• Chemical exposure attacking coatings
• Washdown water reaching threads
• Thermal expansion cycles between day and night operation
• Load reversals through the joint every flight
• Cross-threading and tool damage during field repairs
• Corrosion from fertilizer-laden moisture

That duty cycle is exactly what retires this component. None of these stresses is dramatic on its own — the accumulation is what does it. This is why airframe fasteners are inspection items every time the aircraft frame is opened up, and why operators who run hard keep spares on the shelf.

A healthy screw (m25-hc00400040-050020-0003-n) delivers:

• Factory-correct fit in the aircraft frame — no modification, no adaptation
• Exact OEM behavior the surrounding components were engineered around
• Restored function you can verify on the first post-repair check
• Correct preload and retention at the joint
• One less known-weak point flying through your application window
• Confidence that the repair is done, not patched
• A maintenance log entry with a real DJI part number behind it
• Full compatibility with the parts around it — because it is the part the diagram calls for

Stock the screw (m25-hc00400040-050020-0003-n) before the season does its work, and the aircraft frame never becomes the reason the aircraft sits.

On the T100 the aircraft frame module covers the center-frame structure and the joints where arms, landing gear, and mounting brackets tie into it. A fastener at one of those joints does not simply hold two pieces together; it creates clamp load, and it is the clamp load rather than the screw body that carries flight and landing forces across the joint. When preload drops, the joint starts to move, and the screw begins taking load in shear and bending it was never sized to see.

DJI encodes the characteristics of this fastener in the designation M25-HC00400040-050020-0003-N, but the company does not publish a plain-language key to those fields. That is why this listing states no thread size, length, head height, drive size, or coating grade — a fastener figure that cannot be cited is worse than no figure at all. Order by material number YC.WJ.LL000138 and by the diagram callout, then lay the new screw alongside the one you removed before it goes into the aircraft.

Airframe hardware on a spray drone lives harder than hardware on almost any other machine its size. It sees blade-pass vibration continuously, thermal swing from a cold dawn start to a hot afternoon deck, tank chemistry as drifting mist and as runoff down the frame, and a pressure washer at the end of most working days. Every one of those attacks the same thing: the clamp load that is holding the joint still.

⚙️ Functional Purpose

The screw (m25-hc00400040-050020-0003-n) is designed to do one job in the aircraft frame and do it to specification: tying the airframe together under full payload and full power.

The component:

• Serves the aircraft frame of the DJI Agras T100 exactly as the factory intends
• Supports tying the airframe together under full payload and full power
• Maintains the tolerances and interfaces the surrounding parts depend on
• Withstands the chemical, vibration, and washdown environment of agricultural work
• Holds its torque and preload through vibration
• Keeps failure modes visible and diagnosable instead of mysterious
• Restores factory behavior immediately upon correct installation
• Protects the more expensive components it works alongside
• Carries the exact DJI specification for its position
• Supports safe, predictable operation under full payload
• Eliminates the guesswork of near-fit substitutes
• Keeps the aircraft inside its designed maintenance program
• Holds up across a full season of professional duty

Function on the T100 is a chain: airframe performance depends on the aircraft frame, and the aircraft frame depends on every part in it holding specification. This component is one link in that chain — and chains fail at the worn link, not the average one.

That is why the platform's maintenance philosophy is inspection and renewal, not run-to-failure. The operators with the best uptime records are not the ones with the newest aircraft — they are the ones who replace parts like this when inspection says so, on their own schedule instead of the failure's.

A failing screw (m25-hc00400040-050020-0003-n) costs you:

• Downtime in the middle of an application window — the most expensive hours in agriculture
• Acres not covered while the aircraft waits on a part
• Collateral wear on the components around the failing one
• Diagnostic hours chasing symptoms instead of causes
• Rework when a temporary fix lets go mid-job
• Customer trust when scheduled work slips
• Higher repair bills the longer the fault runs
• Risk exposure every flight the fault remains aboard
• Resale value on an airframe with deferred maintenance

Fix it on your schedule, not the failure's.

Confirming this fastener rather than the joint around it starts with backing it out completely and looking at the threads under good light. Bright, undamaged flanks on a screw that would not hold torque point at the female thread in the frame, not at the screw. Thread material clinging to the flanks, or a fine spiral of swarf coming out with it, means the boss or insert let go. Rolled, flattened, or galled thread crests mean the fastener has already been through an over-torque event and must not go back in.

The second check needs a calibrated driver rather than a wrist. Set it to the value DJI specifies for that position in the T100 maintenance documentation and see whether the fastener will reach it. If it turns steadily and never builds torque, the female thread is gone. If it snaps up to torque normally but a paint stripe drawn across the head and the surrounding surface has broken alignment since the last inspection, the joint is shedding preload in service and the whole clamp stack needs opening up.

The most useful distinction in the field is between a fastener that failed and a joint that is failing. Fit a new screw at the specified torque and fly the job. If it is loose again at the next walkaround, the screw was never the problem — look for a crushed spacer, a compressed composite face under the head, a deformed washer seat, a cracked boss, or a hole that has elongated. Replacing the same screw in the same position three times is the airframe telling you to take the joint apart.

⚠️ Common Replacement Indicators

• Rounded, stripped, or damaged drive recess
• Visible corrosion on head or threads
• Fastener found loose at inspection
• Missing fastener discovered at a walkaround
• Thread damage in the mating part from a failing fastener
• Fretting marks or movement witness at the joint
• Fastener replaced with a wrong-spec substitute during a field fix
• Torque loss on re-check after flights
• Coating worn through and surface rust starting
• Head cracked or deformed from over-torque
• Vibration loosening recurring at the same position
• Any fastener removed more than a few times — replace, not reuse

What kills airframe fasteners: the compounding of ordinary duty. Chemical exposure attacks materials, vibration works at every interface, UV ages every exposed surface, and washdowns drive water at every seam — repeated across hundreds of cycles per season. Add the occasional hard landing or transport knock and the result is predictable: the part that was fine in spring is the failure point by late season.

Replacement and verification: Replacement is a standard shop task on the T100: open access to the aircraft frame, document connections and hardware positions, swap the screw (m25-hc00400040-050020-0003-n) for the OEM unit, and reassemble with attention to seating, routing, and torque. Verify with a function check on the ground before returning to production work.

Confirm before you order: this is DJI part YC.WJ.LL000138. Check the label on your old screw (m25-hc00400040-050020-0003-n) or the position in your official parts diagram and match the number — revision suffixes like .01 or .F on a label are the same part.

Black or reddish dust weeping from the seam around a fastener head, most visible right after a washdown. That is fretting debris, and it means the joint has been moving microscopically under load. The screw has lost preload even if it still feels tight when you put a wrench on it.

A screw found snapped off flush with the surface. That is usually fatigue from running loose rather than a single overload event. Expect to find the neighboring fasteners at the same joint loose or stretched as well, because they were carrying the load the broken one stopped carrying.

The drive recess rounding out on the first attempt at removal. Typically a corroded fastener, a worn or wrong-size bit, or an impact driver used at a previous service. Once the recess is compromised the fastener is scrap: get it out and replace it rather than trying to redress the head and reuse it.

A bend you can see by rolling the removed screw across a flat bench. The shank has taken a shear or impact load, which means something moved at that joint. Check the hole for elongation and the surrounding structure for hard-landing or transport damage before a new fastener goes in.

Loosening that recurs at one position while the identical fasteners around it stay put. That is a joint problem, not a hardware problem. A single position that will not hold clamp load points at a damaged female thread, a crushed spacer, or a cracked boss underneath the surface.

White or green powder around the head, or dark staining running down from it. Washdown water and tank chemistry have been sitting under the head with the coating breached. A corroded fastener is losing section, and it cannot be torque-checked meaningfully because friction has changed everywhere in the joint.

Removal sequence that avoids making things worse: batteries out first, then support whatever the fastener is holding before the last screw at that joint comes loose, so weight never hangs on wiring or on one remaining fastener. Seat the correct-size bit fully, press straight in along the axis of the screw, and break it loose with steady hand pressure. No impact driver.

Refit sequence: blow the female thread clear of grit and dried chemical before anything goes in, and resist running a tap through it unless you know exactly what thread is in there. Start the screw by turning it backwards until you feel the threads drop into the start, then run it in by hand as far as it will go. If it will not run down by hand, stop — forcing it is how a good thread becomes a cut one.

Snug every fastener at the joint lightly first, then bring them to the DJI torque figure in a cross pattern so the part pulls down square instead of tipping onto a corner. It is seated when the head is fully down on its bearing face with no visible gap, the part will not rock under thumb pressure, and the recess is undamaged. Mark the head and the surface with a paint stripe so the next inspection is a two-second look.

If the fastener came out with a colored patch molded onto its threads it carried a pre-applied locking compound, and that patch is largely spent after the first removal. Do not top it up with whatever threadlocker is open on the bench, and never put a high-strength anaerobic compound into a composite or light-alloy boss — on the next removal the insert comes out with the screw.

📐 Specifications

DJI Material Number: YC.WJ.LL000138

Part: Screw (M25-HC00400040-050020-0003-N)

Type: OEM fastener, DJI specification M25-HC00400040-050020-0003-N

Compatibility:

• DJI Agras T100
• Position: the aircraft frame
• Diagram sheet: Aircraft Frame Module (official T100 parts list)

Quantity: 1

Installation Area: The aircraft frame

Function: Tying the airframe together under full payload and full power

Construction: DJI OEM fastener manufactured to the specification encoded in its DJI designation

Application: DJI Agras T100 airframe service and repair

Condition: Brand new

Dimensional data: DJI does not publish a plain-text thread, length, head, or drive breakdown for designation M25-HC00400040-050020-0003-N. Match the fastener you removed and order by material number YC.WJ.LL000138.

Torque specification: Not published in this listing. Use the torque value DJI lists for this position in T100 maintenance documentation or dealer service data. Do not estimate: over-torque strips the female thread, under-torque lets the joint fret itself loose.

Reuse: Treat as a replacement item rather than a reusable one wherever a pre-applied thread-locking patch, visible corrosion, or a previous over-torque event is involved.

Identification method: Match both the DJI designation M25-HC00400040-050020-0003-N and material number YC.WJ.LL000138 against the callout position on the Aircraft Frame Module diagram sheet.

🚜 Necessary For

Built for:

• Professional aerial application businesses running the DJI Agras T100
• Custom applicators covering row crops, orchards, and pasture
• Farm operations running their own spray drone program
• Agricultural service providers with multi-aircraft fleets
• Spray drone fleet maintenance managers
• Agricultural drone repair shops and service centers
• Operators who keep a bench stock of wear parts
• Rice, corn, soybean, and wheat growers using aerial application
• Orchard and vineyard spray operations
• Pasture and rangeland weed control operators
• Cover crop seeding operations using the spreading system
• Precision agriculture consultants supporting drone fleets
• Dealers and technicians maintaining customer aircraft
• Operators running dawn-to-dusk during application windows
• Anyone restoring a DJI Agras T100 to factory-correct condition

Especially valuable during:

• Pre-season maintenance and rebuild windows before spray campaigns begin
• Peak spray season, when a grounded aircraft costs acres per hour
• Fungicide application windows measured in days, not weeks
• Late-season spreading and cover crop seeding work
• Post-season teardown, inspection, and winterization
• Fleet inspections after a hard landing or transport damage
• Pre-contract equipment checks before custom application work
• Mid-season turnarounds where the machine has to fly tomorrow

If the DJI Agras T100 earns its keep on your operation, this component belongs on your parts shelf before it belongs on your aircraft. The time to buy it is before the season, not during the failure.

Rebuilding an airframe joint properly after a hard landing or a transport knock, where the correct move is new hardware at every position that was disturbed rather than reusing fasteners that have already absorbed an overload and lost the preload they were installed with.

Restocking the hardware drawer ahead of a season, so a walkaround that turns up a missing, corroded, or rounded fastener ends in a five-minute replacement on the tailgate instead of a grounded aircraft waiting on a screw while an application window closes.

💡 Why This Part Matters

Every acre the T100 covers depends on the aircraft frame doing its job — and the aircraft frame depends on parts exactly like this one.

The economics are simple. The DJI Agras T100 exists to cover ground during windows that do not wait — and every hour it sits, the work either doesn't happen or happens on someone else's schedule. A failed screw (m25-hc00400040-050020-0003-n) is rarely expensive because of what the part costs; it is expensive because of when it fails. Parts fail during use, and use happens during the season.

That is the case for OEM and the case for stocking ahead. The OEM component fits the first time, behaves the way the platform expects, and carries the exact specification the airframe was engineered around — DJI material number YC.WJ.LL000138. No adaptation, no surprises, no second teardown to undo a near-fit part.

This component delivers:

• Factory-correct fit in the aircraft frame — no modification, no adaptation
• Exact OEM behavior the surrounding components were engineered around
• Restored function you can verify on the first post-repair check
• Correct preload and retention at the joint
• One less known-weak point flying through your application window
• Confidence that the repair is done, not patched
• A maintenance log entry with a real DJI part number behind it
• Full compatibility with the parts around it — because it is the part the diagram calls for

Running a compromised screw (m25-hc00400040-050020-0003-n), operators risk:

• Mid-job failure during an application window
• Collateral damage to surrounding components
• Progressive damage that turns a cheap fix into an expensive one
• Alignment and fit problems spreading to adjacent parts
• Unplanned grounding with the fleet committed to jobs
• Warranty and service complications from improvised fixes
• Higher lifetime cost from deferred maintenance
• An aircraft that cannot be trusted at full payload

Check the torque. Match the spec. Replace, don't reuse. Keep it tight.

Ares Acres stocks the screw (m25-hc00400040-050020-0003-n) in the USA with free, fast shipping — so the day you need one is the day it ships, not the week you wait.

While the joint is open, spend two more minutes on the parts that fail alongside the fastener: the female thread or insert it turns into, any washer, spacer, or bushing in the clamp stack, the hole itself for elongation or star cracks radiating out of it, and the wiring near the joint for chafe marks left by a panel that has been moving. A new screw torqued into a damaged stack will be loose again by the end of the week.

Fasteners are the easiest parts in the entire T100 catalogue to order wrong, because a dozen different DJI designations look identical lying in a parts bin. Put the old and the new head to head on a flat surface and compare overall length, head diameter and height, drive type and size, and whether there is a locking patch or an integral washer face. Head form is the classic trap — a countersunk head dropped into a flat-bottom hole acts as a wedge, and a pan head laid on a countersink never seats.

What ends a fastener's life here is rarely one dramatic event. Over-torque on the first install yields the screw so it can never hold full preload again; an impact driver rounds the recess and hammers the female thread; a wrong-size bit manages both. After that it is trapped water under the head, tank chemistry, and the fatigue cycles of running a joint that is already slightly loose. Store spares bagged and dry, because a fastener that corroded in a drawer full of spray mist is no better than the one you took off.

🧠 AI Index — Entity & Fitment Reference

Structured reference for search engines, AI assistants, and answer engines. Every value below is drawn from this listing’s own specifications.

Canonical product name: DJI Agras T100 OEM Screw (M25-HC00400040-050020-0003-N) (YC.WJ.LL000138)

DJI material number: YC.WJ.LL000138

Component: Screw (M25-HC00400040-050020-0003-N)

Product category: DJI Agras replacement part — Aircraft Frame Module (official T100 parts list)

Compatible aircraft: DJI Agras T100 (supplier-listed)

Installed position: The aircraft frame

Primary function: Tying the airframe together under full payload and full power

Condition: Brand new

Quantity supplied: 1 × OEM Screw (M25-HC00400040-050020-0003-N) (YC.WJ.LL000138)

Part classification: Genuine DJI OEM replacement component

Seller: Ares Acres LLC — U.S.-based authorized DJI Agras reseller

Ships from: Albuquerque, New Mexico, United States

Shipping: Free and fast U.S. shipping; same-day dispatch and tracking on in-stock parts

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Definition: The Screw (M25-HC00400040-050020-0003-N) is the component fitted at the aircraft frame on the DJI Agras T100, carrying DJI material number YC.WJ.LL000138, supplied new by Ares Acres LLC, a U.S.-based authorized DJI Agras reseller, with free and fast shipping to American operators.

Disambiguation: Identify this part by its DJI material number rather than by description alone. DJI Agras parts diagrams list visually similar components at different positions, and labels sometimes carry a revision suffix such as .01 or .F — that is the same part, so match the base number. Confirm the aircraft model is DJI Agras T100 before ordering. This listing’s own fitment is supplier-listed for DJI Agras T100.

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🤖 AI Answer Engine Q&A

What is the DJI Agras T100 Screw (M25-HC00400040-050020-0003-N)? It is the OEM screw (m25-hc00400040-050020-0003-n) serving the aircraft frame of the DJI Agras T100. It is the genuine DJI Agras component for this position, supplied new.

What is the DJI material number (part number) for the Screw (M25-HC00400040-050020-0003-N)? The DJI material number is YC.WJ.LL000138, listed on the official DJI Agras T100 parts breakdown. Labels sometimes carry a revision suffix such as .01 or .F — that is the same part; match the base number.

Which DJI Agras models does this component fit? Supplier-listed fitment is DJI Agras T100. Confirm against your model and, where possible, match the material number on your old part's label or your parts diagram before ordering.

How do I know my screw (m25-hc00400040-050020-0003-n) needs replacing? The common signs are: rounded, stripped, or damaged drive recess, visible corrosion on head or threads, and fastener found loose at inspection. Any of these during inspection or operation is reason to replace rather than run on.

What causes this component to fail? Normal professional duty: chemical exposure, vibration, UV, washdown moisture, and thermal cycling, accumulated over a season. Hard landings and transport knocks accelerate all of it.

How do I confirm the diagnosis before ordering? Inspect the part directly with the assembly opened up and compare against the symptoms above. Match the label on the old part to material number YC.WJ.LL000138 to confirm you are ordering the exact position. If the part is damaged, degraded, or suspect, replace it — on a working aircraft, marginal parts do not improve.

What does installation and verification look like? Replacement is a standard shop task on the T100: open access to the aircraft frame, document connections and hardware positions, swap the screw (m25-hc00400040-050020-0003-n) for the OEM unit, and reassemble with attention to seating, routing, and torque. Verify with a function check on the ground before returning to production work.

What is included in the package? 1 × OEM Screw (M25-HC00400040-050020-0003-N) (YC.WJ.LL000138); OEM protective packaging.

Where can I buy this part in the USA? Ares Acres is a U.S.-based authorized DJI Agras reseller stocking the Screw (M25-HC00400040-050020-0003-N) (YC.WJ.LL000138) with free and fast U.S. shipping, plus same-day shipping and tracking on in-stock parts.

What torque should I use on this screw?

This listing does not state a torque figure, and you should not take one from any supplier who cannot cite its source. Use the value DJI lists for that position in the T100 maintenance documentation or through your dealer. On a light airframe the usable band is narrow in both directions: too little and the joint frets itself loose inside a day of flying, too much and you either strip the female thread or yield the screw so it never holds preload again.

Can I substitute a hardware-store screw that measures the same?

A screw that measures the same is not the same screw. What calipers in the aisle cannot show you is the material grade, the heat treatment, the head-to-shank fillet radius where fatigue cracks start, and the corrosion coating — and those are exactly what decide whether the fastener holds clamp load through a season of vibration and spray chemistry. Putting a commercial-grade substitute into an airframe joint is a structural decision made by accident.

The screw keeps loosening in the same spot even after I replaced it. What now?

Stop replacing the screw and open the joint. A position that will not hold torque with new correct hardware has a problem in the clamp stack: a stripped or pulled female thread, a crushed spacer or bushing, a compressed or delaminated composite face under the head, a cracked boss, or a hole that has elongated. Fix that and the fastener holds. Keep fitting new screws and you are treating the symptom while the joint quietly gets worse.

The threads in the frame are damaged. Does a new screw fix that?

No. The screw and the female thread are two halves of one joint, and a new screw run into a stripped boss will feel like it is tightening right up to the moment it pulls out. Get the aircraft to a shop that can assess the boss or insert properly. Running a tap through by eye is how a slightly damaged thread becomes an oversized one that no correct-specification fastener will ever hold again.

Should I add threadlocker when I fit it?

Only what DJI calls for at that position. If the fastener you removed had a colored patch molded onto the threads, it was supplied with a pre-applied locking compound and a new fastener is the right way to restore that function. Adding a high-strength anaerobic compound of your own into a composite or light-alloy boss usually means that at the next removal the insert comes out of the frame still attached to the screw.

Can I use an impact driver to break it loose?

Not on this hardware. An impact driver delivers rotational hammer blows that round a drive recess faster than anything else in the toolbox, and it has no feel at all, so it will happily keep going after the female thread has started to strip. Use a correctly sized bit, press hard along the axis of the screw, and break it loose with steady hand pressure. If it is seized, the answer is penetrant and patience, not more hammer.

How many of these do I need for my repair?

This is supplied as one fastener. The quantity your position takes comes off the Aircraft Frame Module sheet of the official T100 parts list. Count the callouts at the joint rather than counting what is currently in the aircraft, because a previous field repair may have left a position short or filled it with a substitute. When a joint has been disturbed by an overload, ordering enough to renew every fastener at that joint is cheaper than a second teardown.

What does the designation M25-HC00400040-050020-0003-N actually mean?

It is a DJI internal fastener specification code, and its fields encode the characteristics of the part — form, thread, dimensions, and finish. DJI does not publish a plain-language key to those fields, so there is no honest way to convert the code into a thread size and length for you here. That is exactly why material number YC.WJ.LL000138 and the diagram position are the identifiers to order by, and why you compare old against new on the bench.