The Washer,recessed, cataloged under National Stock Number 5310-01-101-1856, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. Government technical data includes 11 specifications, cited from the U.S. Government catalog. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-01-101-1856 |
| Item Name | Washer,recessed |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Status | ACTIVE |
| Surface Treatment Document and Classification | QQ-P-416,TYPE 2,CLASS 2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Hardness Rating | 39.0 ROCKWELL C MINIMUM AND 45.0 ROCKWELL C MAXIMUM |
| Style Designator | RECESSED |
| Material Document and Classification | MIL-S-6758 MIL SPEC 1ST MATERIAL RESPONSE AND MIL-S-18729 MIL SPEC 2ND MATERIAL RESPONSE OVERALL |
| Outside Diameter | 0.702 INCHES MINIMUM AND 0.712 INCHES MAXIMUM IN |
| Material Thickness | 0.071 INCHES MINIMUM AND 0.085 INCHES MAXIMUM IN |
| Recess Diameter | 0.497 INCHES MINIMUM AND 0.507 INCHES MAXIMUM IN |
| Surface Treatment | CADMIUM OVERALL |
| Material | STEEL COMP 4130 OVERALL |
| Hole Diameter | 0.376 INCHES MINIMUM AND 0.380 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 |
| Reference | Meaning |
|---|---|
| MS21299-C6 | C/1 Advisory reference — outside the item-of-supply concept Zf Industrieantriebe Witten Gmbh |
| MS21299C6 | 3/2 Design control — primary reference U.S. Government activity |
| MS21299C6 | 5/9 Secondary reference U.S. Government activity |
NSN 5310-01-101-1856 is a Washer,recessed, classified under FSC 5310, Nuts and Washers. Status: active.
1 possible match (shared part number, not a government interchangeability claim): 5310-01-497-8368. Verify interchangeability with system specifications before substitution.
Key specifications for 5310-01-101-1856: Surface Treatment Document and Classification: QQ-P-416,TYPE 2,CLASS 2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Hardness Rating: 39.0 ROCKWELL C MINIMUM AND 45.0 ROCKWELL C MAXIMUM; Style Designator: RECESSED; Material Document and Classification: MIL-S-6758 MIL SPEC 1ST MATERIAL RESPONSE AND MIL-S-18729 MIL SPEC 2ND MATERIAL RESPONSE OVERALL. 11 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.