The Nut,self-Locking,extended Washer, cataloged under National Stock Number 5310-01-375-7165, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Sps Technologies, Llc Dba PB Fasteners. Government technical data includes 17 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-01-375-7165 |
| Primary Part Number | RMLH18-4 |
| Item Name | Nut,self-Locking,extended Washer |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Sps Technologies, Llc Dba PB Fasteners |
| Status | ACTIVE |
| Lubrication | DRY FILM LUBRICANT |
| Washer Outside Diameter | 0.434 INCHES MAXIMUM IN |
| Width Across Flats | 0.347 INCHES MINIMUM IN |
| Surface Treatment Document and Classification | QQ-P-416,TY2,CL3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Series | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Temp Rating | 450.0 FAHRENHEIT NOMINAL DEGF |
| Hardness Rating | 40.0 ROCKWELL C MINIMUM AND 44.0 ROCKWELL C MAXIMUM |
| Washer Thickness | 0.040 INCHES NOMINAL IN |
| Material Document and Classification | AMS 6304 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Thread Direction | RIGHT-HAND |
| Nominal Thread Size | 0.250 INCHES IN |
| Locking Feature | PREVAILING TORQUE ALL METAL DESIGN |
| Surface Treatment | CADMIUM AND CHROMATE OVERALL |
| Nut Style | DOUBLE HEXAGON |
| Thread Class | 3B |
| Thread Quantity Per Inch | 28 |
| Material | STEEL COMP 601 OVERALL |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| RMLH18-4 PRIMARY | Sps Technologies, Llc Dba PB Fasteners (USA) |
| Reference | Meaning |
|---|---|
| RMLH18-4 | 5/9 Secondary reference Harvard Industries Inc |
NSN 5310-01-375-7165 is a Nut,self-Locking,extended Washer, manufactured by Sps Technologies, Llc Dba PB Fasteners, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-375-7165 has 1 manufacturer part number on file: RMLH18-4 (Sps Technologies, Llc Dba PB Fasteners).
Key specifications for RMLH18-4: Lubrication: DRY FILM LUBRICANT; Overall Height: 0.250 INCHES MAXIMUM IN; Washer Outside Diameter: 0.434 INCHES MAXIMUM IN; Width Across Flats: 0.347 INCHES MINIMUM IN. 17 specifications are documented in the U.S. Government catalog.
No hazard code in the DLA record (HMIC N). Hazard information on this page is shown exactly as it appears in the DLA record.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-16.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.