The Washer,flat, cataloged under National Stock Number 5310-01-169-1553, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Barber-Colman Co Environmental Controls Div. Government technical data includes 8 specifications, cited from the U.S. Government catalog. The record lists 2 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 | 5310-01-169-1553 |
| Primary Part Number | W1-61 |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Barber-Colman Co Environmental Controls Div |
| Status | ACTIVE |
| Overall Diameter | 0.865 INCHES MINIMUM AND 0.870 INCHES MAXIMUM IN |
| Cross-Sectional Shape Style | RECTANGULAR |
| Surface Treatment | PASSIVATE OVERALL |
| Peripheral Shape Style | ROUND |
| Material | STEEL COMP 631 OVERALL |
| Center Hole Shape Style | ROUND |
| Hole Diameter | 0.625 INCHES MINIMUM AND 0.635 INCHES MAXIMUM IN |
| Thickness | 0.022 INCHES MINIMUM AND 0.028 INCHES MAXIMUM IN |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
NSN 5310-01-169-1553 is a Washer,flat, manufactured by Barber-Colman Co Environmental Controls Div, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-169-1553 has 2 manufacturer part numbers on file: W1-61 (Barber-Colman Co Environmental Controls Div), W1-61 (Ge Aviation Systems Llc Dba Ge Aviation Systems Llc).
1 possible match (shared part number, not a government interchangeability claim): 6515-01-213-9525. Verify interchangeability with system specifications before substitution.
Key specifications for W1-61: Overall Diameter: 0.865 INCHES MINIMUM AND 0.870 INCHES MAXIMUM IN; Cross-Sectional Shape Style: RECTANGULAR; Surface Treatment: PASSIVATE OVERALL; Peripheral Shape Style: ROUND. 8 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.