The Washer,shouldered and Recessed, cataloged under National Stock Number 5310-01-303-9655, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Rtx Corporation Div Pratt & Whitney. 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 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 | 5310-01-303-9655 |
| Primary Part Number | 166404-1 |
| Item Name | Washer,shouldered and Recessed |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Rtx Corporation Div Pratt & Whitney |
| Status | ACTIVE |
| Surface Treatment Document and Classification | ASTM B633,TY 2,CL 2 ASSN STD SINGLE TREATMENT RESPONSE OVERALL |
| Shoulder Height | 0.045 INCHES NOMINAL IN |
| Material Document and Classification | AMS 5045 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Outside Diameter | 0.735 INCHES MINIMUM AND 0.765 INCHES MAXIMUM IN |
| Recess Depth | 0.040 INCHES MINIMUM AND 0.050 INCHES MAXIMUM IN |
| Material Thickness | 0.060 INCHES NOMINAL IN |
| Surface Treatment | ZINC AND CHROMATE OVERALL |
| Material | STEEL COMP 1020 OVERALL |
| Hole Diameter | 0.192 INCHES MINIMUM AND 0.196 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 |
| Part Number | Manufacturer |
|---|---|
| 166404-1 PRIMARY | Rtx Corporation Div Pratt & Whitney (USA) |
NSN 5310-01-303-9655 is a Washer,shouldered and Recessed, manufactured by Rtx Corporation Div Pratt & Whitney, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-303-9655 has 1 manufacturer part number on file: 166404-1 (Rtx Corporation Div Pratt & Whitney).
1 possible match (shared part number, not a government interchangeability claim): 6525-01-718-5196. Verify interchangeability with system specifications before substitution.
Key specifications for 166404-1: Surface Treatment Document and Classification: ASTM B633,TY 2,CL 2 ASSN STD SINGLE TREATMENT RESPONSE OVERALL; Shoulder Height: 0.045 INCHES NOMINAL IN; Material Document and Classification: AMS 5045 ASSN STD SINGLE MATERIAL RESPONSE OVERALL; Outside Diameter: 0.735 INCHES MINIMUM AND 0.765 INCHES MAXIMUM IN. 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.