The Washer,keyway, cataloged under National Stock Number 5310-00-883-2957, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Hydro-Aire Aerospace Corp. Dba Lear Romec Div Lear Romec. 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 | 5310-00-883-2957 |
| Primary Part Number | RB21739 |
| Item Name | Washer,keyway |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Hydro-Aire Aerospace Corp. Dba Lear Romec Div Lear Romec |
| Status | ACTIVE |
| Distance From Centerline to Bottom of Internal Keyway | 0.255 INCHES MINIMUM AND 0.260 INCHES MAXIMUM IN |
| Internal Keyway Width | 0.096 INCHES MINIMUM AND 0.098 INCHES MAXIMUM IN |
| Surface Finish | 12.0 MICROINCHES BOTTOM |
| Surface Finish | 12.0 MICROINCHES TOP |
| Surface Treatment Document and Classification | QQ-C-320 CL 2E FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Material Document and Classification | ASTM A320-63 GR L10 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Outside Diameter | 0.855 INCHES NOMINAL IN |
| Internal Keyway Quantity | 2 |
| Material Thickness | 0.126 INCHES MINIMUM AND 0.128 INCHES MAXIMUM IN |
| Surface Treatment | CHROMIUM OVERALL |
| Material | STEEL COMP 630 OVERALL |
| Hole Diameter | 0.377 INCHES MINIMUM AND 0.378 INCHES MAXIMUM 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 |
|---|---|
| RB21739 PRIMARY | Hydro-Aire Aerospace Corp. Dba Lear Romec Div Lear Romec (USA) |
NSN 5310-00-883-2957 is a Washer,keyway, manufactured by Hydro-Aire Aerospace Corp. Dba Lear Romec Div Lear Romec, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-00-883-2957 has 1 manufacturer part number on file: RB21739 (Hydro-Aire Aerospace Corp. Dba Lear Romec Div Lear Romec).
Key specifications for RB21739: Distance From Centerline to Bottom of Internal Keyway: 0.255 INCHES MINIMUM AND 0.260 INCHES MAXIMUM IN; Internal Keyway Width: 0.096 INCHES MINIMUM AND 0.098 INCHES MAXIMUM IN; Surface Finish: 12.0 MICROINCHES BOTTOM; Surface Finish: 12.0 MICROINCHES TOP. 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.