Prime-Line
Prime-Line 9118861 Lock Nut 1/4"-20 Steel Zinc 50 PK
Hex nut with a built-in free-spinning external tooth lock washer, 1/4"-20 thread, steel zinc plated, 50 pack
- TypeNuts
- Size1/4"-20
- Built-in lock washer bites into surfaces for secure fastening
- 50-piece pack supplies enough hardware for multiple projects
- Coarse UNC-2B threads fit standard 1/4"-20 bolts and rods
- Zinc-plated steel resists corrosion in automotive and general use
- Meets ASME B1.1 specification for thread quality and dimensions
Prime-Line 9118861 Kep Nuts
These Prime-Line 9118861 lock nuts integrate a free-spinning external tooth washer that bites into the mating surface to resist vibration loosening. The 1/4"-20 UNC-2B coarse threads fit standard bolts, cap screws or threaded rod of the same size. They install with a regular wrench or socket set just like a conventional hex nut. The 50-piece pack covers multiple fastening points in a single purchase.
Built-In Lock Washer Benefit
The captive washer eliminates the need to handle a separate lock washer during assembly, reducing dropped parts and speeding installation. Because the washer spins freely, it seats evenly without twisting the nut off-thread. The teeth engage the workpiece directly, providing a mechanical lock that does not rely on prevailing torque or adhesive compounds.
Steel Zinc Construction and ASME B1.1 Compliance
Zinc-plated steel offers corrosion resistance for indoor and sheltered outdoor use while maintaining the strength of a Grade 2 fastener. The nuts meet ASME B1.1 thread standards, ensuring consistent fit with mating hardware from any compliant source. Buyers who need stainless steel for marine environments or a finer thread pitch for precision adjustment should look elsewhere.
Highlights
- Built-in lock washer bites into surfaces for secure fastening
- 50-piece pack supplies enough hardware for multiple projects
- Coarse UNC-2B threads fit standard 1/4"-20 bolts and rods
- Zinc-plated steel resists corrosion in automotive and general use
- Meets ASME B1.1 specification for thread quality and dimensions
Specifications
| Brand | PRIME-LINE |
|---|---|
| Type | Nuts |
| Size | 1/4"-20 |
Questions about this item
Will the zinc plating on these 1/4"-20 lock nuts wear off and require replacement?
The zinc plating provides corrosion resistance for the steel nuts; replacement is only needed if the threads strip or the external tooth lock washer teeth no longer bite into the mating surface.
What is the first limit reached when these K-lock nuts are torqued repeatedly?
The limiting factor is the coarse UNC-2B thread engagement; over-torquing can strip the 1/4"-20 threads before the free-spinning external tooth lock washer loses its grip.
Do these nuts generate heat or noise when left under constant vibration all day?
As passive steel fasteners they produce no heat or noise themselves; the external tooth lock washer simply maintains clamping force against vibration without any power draw.
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