The Washer,recessed, cataloged under National Stock Number 5310-01-264-3615, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Lockheed Martin Corp. Government technical data includes 9 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 5310-01-264-3615 |
| Primary Part Number | 21D5C10C |
| Item Name | Washer,recessed |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Lockheed Martin Corp |
| Status | ACTIVE |
| Style Designator | RECESSED |
| Material Document and Classification | AMS 5525 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Outside Diameter | 1.052 INCHES MINIMUM AND 1.072 INCHES MAXIMUM IN |
| Material Thickness | 0.068 INCHES MINIMUM AND 0.088 INCHES MAXIMUM IN |
| Recess Diameter | 0.785 INCHES MAXIMUM IN |
| Surface Treatment | PASSIVATE OVERALL |
| Material | IRON ALLOY 660 OVERALL |
| Hole Diameter | 0.631 INCHES MINIMUM AND 0.643 INCHES MAXIMUM IN |
| Recess Angle | 90.0 DEGREES NOMINAL |
| 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 |
|---|---|
| 21D5C10C | Lockheed Martin Corp (USA) |
| Reference | Meaning |
|---|---|
| VN900-10C | 3/2 Design control — primary reference U.S. Government activity |
NSN 5310-01-264-3615 is a Washer,recessed, manufactured by Lockheed Martin Corp, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-264-3615 has 1 manufacturer part number on file: 21D5C10C (Lockheed Martin Corp).
Key specifications for 21D5C10C: Style Designator: RECESSED; Material Document and Classification: AMS 5525 ASSN STD SINGLE MATERIAL RESPONSE OVERALL; Outside Diameter: 1.052 INCHES MINIMUM AND 1.072 INCHES MAXIMUM IN; Material Thickness: 0.068 INCHES MINIMUM AND 0.088 INCHES MAXIMUM IN. 9 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.