The Washer,flat, cataloged under National Stock Number 5310-01-331-7228, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Interspiro Inc. Government technical data includes 6 specifications, cited from the U.S. Government catalog. The record lists 3 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 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 | 5310-01-331-7228 |
| Primary Part Number | 336-100-437 |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Interspiro Inc |
| Status | ACTIVE |
| Overall Diameter | 12.0 MILLIMETERS NOMINAL MM |
| Cross-Sectional Shape Style | RECTANGULAR |
| Peripheral Shape Style | ROUND |
| Material | PLASTIC PHENOL FORMALDEHYDE (PMO) OVERALL |
| Center Hole Shape Style | ROUND |
| Thickness | 0.7 MILLIMETERS MINIMUM AND 1.3 MILLIMETERS MAXIMUM MM |
| 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 |
|---|---|
| 336-100-437 PRIMARY | Interspiro Inc (USA) |
| 336-190-638 PRIMARY | Interspiro Inc (USA) |
| 6318026 | Naval Sea Systems Command (USA) |
NSN 5310-01-331-7228 is a Washer,flat, manufactured by Interspiro Inc, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-331-7228 has 3 manufacturer part numbers on file: 336-100-437 (Interspiro Inc), 336-190-638 (Interspiro Inc), 6318026 (Naval Sea Systems Command).
1 possible match (shared part number, not a government interchangeability claim): 5331-01-551-8813. Verify interchangeability with system specifications before substitution.
Key specifications for 336-100-437: Overall Diameter: 12.0 MILLIMETERS NOMINAL MM; Cross-Sectional Shape Style: RECTANGULAR; Peripheral Shape Style: ROUND; Material: PLASTIC PHENOL FORMALDEHYDE (PMO) OVERALL. 6 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.