The Washer,concave, cataloged under National Stock Number 5310-00-280-3608, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Hi-Shear Corporation. Government technical data includes 10 specifications, cited from the U.S. Government catalog. The record lists 4 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-00-280-3608 |
| Primary Part Number | HL776-8PBW |
| Item Name | Washer,concave |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Hi-Shear Corporation |
| Status | ACTIVE |
| Surface Treatment Document and Classification | QQ-P-416,TYPE 2,CLASS 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Radius | 0.260 INCHES NOMINAL IN |
| Style Designator | CONCAVE |
| Material Document and Classification | AMS5520 ASSN STD 1ST MATERIAL RESPONSE OR AMS5643 ASSN STD 2ND MATERIAL RESPONSE OR AMS5528 ASSN STD 3RD MATERIAL RESPONSE OVERALL |
| Outside Diameter | 0.495 INCHES MINIMUM AND 0.505 INCHES MAXIMUM IN |
| Recess Depth | 0.095 INCHES NOMINAL IN |
| Material Thickness | 0.160 INCHES MINIMUM AND 0.170 INCHES MAXIMUM IN |
| Surface Treatment | CADMIUM AND CHROMATE OVERALL |
| Material | STEEL COMP 630 OR STEEL COMP 631 OR STEEL COMP 632 OVERALL |
| Hole Diameter | 0.370 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 |
|---|---|
| HL776-8PBW | Sps Technologies, Llc Dba PB Fasteners (USA) |
| HL776-8PBW | West Coast Aerospace, Inc. (USA) |
| HL776-8PBW | Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company (USA) |
| HL776-8PBW PRIMARY | Hi-Shear Corporation (USA) |
| Reference | Meaning |
|---|---|
| HL776-8PBW | 5/2 Secondary reference U.S. Government activity |
| HL776-8PBW | 5/9 Secondary reference Sps Technologies Inc |
| HL776-8PBW | 5/9 Secondary reference U.S. Government activity |
NSN 5310-00-280-3608 is a Washer,concave, manufactured by Hi-Shear Corporation, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-00-280-3608 has 4 manufacturer part numbers on file: HL776-8PBW (Sps Technologies, Llc Dba PB Fasteners), HL776-8PBW (West Coast Aerospace, Inc.), HL776-8PBW (Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company), HL776-8PBW (Hi-Shear Corporation).
Key specifications for HL776-8PBW: Surface Treatment Document and Classification: QQ-P-416,TYPE 2,CLASS 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Radius: 0.260 INCHES NOMINAL IN; Style Designator: CONCAVE; Material Document and Classification: AMS5520 ASSN STD 1ST MATERIAL RESPONSE OR AMS5643 ASSN STD 2ND MATERIAL RESPONSE OR AMS5528 ASSN STD 3RD MATERIAL RESPONSE OVERALL. 10 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.