The Washer,key, cataloged under National Stock Number 5310-01-265-9333, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Ara, Inc. Government technical data includes 12 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. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-01-265-9333 |
| Primary Part Number | B3878-1 |
| Item Name | Washer,key |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Ara, Inc |
| Status | ACTIVE |
| Surface Treatment Document and Classification | QQ-P-416,TY 2,CL 1 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Distance From Centerline to Inside of Prebent Key | 0.785 INCHES NOMINAL IN |
| External Prebent Key Length | 0.125 INCHES NOMINAL IN |
| Overall Distance Including Keys | 1.325 INCHES NOMINAL IN |
| Material Document and Classification | MIL-S-18729 MIL SPEC SINGLE MATERIAL RESPONSE OR AMS 6350 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Material Thickness | 0.040 INCHES NOMINAL IN |
| Distance From Centerline to End of Key | 0.825 INCHES NOMINAL IN |
| Surface Treatment | CADMIUM AND CHROMATE OVERALL |
| Minimum Tensile Strength | 180000 POUNDS PER SQUARE INCH LBS |
| External Prebent Key Width | 0.400 INCHES NOMINAL IN |
| Material | STEEL COMP 4130 OVERALL |
| Hole Diameter | 0.640 INCHES NOMINAL IN |
| 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 |
|---|---|
| B3878-1 PRIMARY | Ara, Inc (USA) |
NSN 5310-01-265-9333 is a Washer,key, manufactured by Ara, Inc, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-265-9333 has 1 manufacturer part number on file: B3878-1 (Ara, Inc).
Key specifications for B3878-1: Surface Treatment Document and Classification: QQ-P-416,TY 2,CL 1 FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Distance From Centerline to Inside of Prebent Key: 0.785 INCHES NOMINAL IN; External Prebent Key Length: 0.125 INCHES NOMINAL IN; Overall Distance Including Keys: 1.325 INCHES NOMINAL IN. 12 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.