The Washer,flat, cataloged under National Stock Number 5310-01-553-7729, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Hayes Bolt & Supply, Inc. Dba Hayes Bolt & Supply Inc. Government technical data includes 2 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 5310-01-553-7729 |
| Primary Part Number | 31NWHD0Y |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Hayes Bolt & Supply, Inc. Dba Hayes Bolt & Supply Inc |
| Status | ACTIVE |
| Center Hole Shape Style | ROUND |
| Hole Diameter | 0.500 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 |
|---|---|
| 31NWHD0Y PRIMARY | Hayes Bolt & Supply, Inc. Dba Hayes Bolt & Supply Inc (USA) |
| Reference | Meaning |
|---|---|
| 0333628 REV G ITEM 40 | 5/9 Secondary reference Naval Electronic Systems Engineering Center |
NSN 5310-01-553-7729 is a Washer,flat, manufactured by Hayes Bolt & Supply, Inc. Dba Hayes Bolt & Supply Inc, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-553-7729 has 1 manufacturer part number on file: 31NWHD0Y (Hayes Bolt & Supply, Inc. Dba Hayes Bolt & Supply Inc).
Key specifications for 31NWHD0Y: Part Name Assigned by Controlling Agency: WASHER, FLAT, SAE HARDENED; End Item Identification: OK-312A/TSQ-120B, CONTROL GROUP A; Center Hole Shape Style: ROUND; Hole Diameter: 0.500 INCHES NOMINAL IN. 2 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.