The Washer,flat, cataloged under National Stock Number 5310-01-531-6129, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Department of Defense Project Manager-Mobile Electric Power. 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-01-531-6129 |
| Primary Part Number | 88-20556-5A |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Department of Defense Project Manager-Mobile Electric Power |
| Status | ACTIVE |
| Overall Diameter | 0.487 INCHES NOMINAL IN |
| Material Document and Classification | ASME B18.21.1, UNS G10600 THRU G10800 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Cross-Sectional Shape Style | RECTANGULAR |
| Surface Treatment | PHOSPHATE OVERALL |
| Peripheral Shape Style | ROUND |
| Material | STEEL OVERALL |
| Center Hole Shape Style | ROUND |
| Hole Diameter | 0.256 INCHES NOMINAL IN |
| Thickness | 0.062 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 |
|---|---|
| 88-20556-5A PRIMARY | Department of Defense Project Manager-Mobile Electric Power (USA) |
| Reference | Meaning |
|---|---|
| 88-20556 | D/9 Drawing number reference only Department of Defense Project Manager-Mobile Electric Power |
NSN 5310-01-531-6129 is a Washer,flat, manufactured by Department of Defense Project Manager-Mobile Electric Power, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-531-6129 has 1 manufacturer part number on file: 88-20556-5A (Department of Defense Project Manager-Mobile Electric Power).
2 possible matches (shared part number, not a government interchangeability claim): 5310-01-532-0343, 5310-01-533-5198. Verify interchangeability with system specifications before substitution.
Key specifications for 88-20556-5A: Overall Diameter: 0.487 INCHES NOMINAL IN; Material Document and Classification: ASME B18.21.1, UNS G10600 THRU G10800 ASSN STD SINGLE MATERIAL RESPONSE OVERALL; Cross-Sectional Shape Style: RECTANGULAR; Surface Treatment: PHOSPHATE OVERALL. 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.