The Washer,flat, cataloged under National Stock Number 5310-00-256-6325, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Sikorsky Aircraft Corporation Dba Sikorsky Aircraft Corp. Government technical data includes 13 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. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-00-256-6325 |
| Primary Part Number | S1535-61262-7 |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Sikorsky Aircraft Corporation Dba Sikorsky Aircraft Corp |
| Status | ACTIVE |
| Surface Finish | 100.0 MICROINCHES ALL SURFACES |
| Surface Treatment Document and Classification | QQ-S-365,TYPE 1,GRADE A FED SPEC SINGLE TREATMENT RESPONSE OR SS8488,FSCM 78286 MFR REF SINGLE TREATMENT RESPONSE OVERALL |
| Overall Diameter | 1.240 INCHES MINIMUM AND 1.260 INCHES MAXIMUM IN |
| Hardness Rating | 34.0 ROCKWELL C MINIMUM AND 38.0 ROCKWELL C MAXIMUM |
| Material Document and Classification | MIL-S-18729,COND N MIL SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Cross-Sectional Shape Style | RECTANGULAR |
| Surface Treatment | SILVER OR NICKEL AND CADMIUM OVERALL |
| Minimum Tensile Strength | 150000 POUNDS PER SQUARE INCH LBS |
| Peripheral Shape Style | ROUND |
| Material | STEEL COMP 4130 OVERALL |
| Center Hole Shape Style | ROUND |
| Hole Diameter | 0.499 INCHES MINIMUM AND 0.531 INCHES MAXIMUM IN |
| Thickness | 0.045 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 |
|---|---|
| S1535-61262-7 PRIMARY | Sikorsky Aircraft Corporation Dba Sikorsky Aircraft Corp (USA) |
NSN 5310-00-256-6325 is a Washer,flat, manufactured by Sikorsky Aircraft Corporation Dba Sikorsky Aircraft Corp, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-00-256-6325 has 1 manufacturer part number on file: S1535-61262-7 (Sikorsky Aircraft Corporation Dba Sikorsky Aircraft Corp).
Key specifications for S1535-61262-7: Surface Finish: 100.0 MICROINCHES ALL SURFACES; Surface Treatment Document and Classification: QQ-S-365,TYPE 1,GRADE A FED SPEC SINGLE TREATMENT RESPONSE OR SS8488,FSCM 78286 MFR REF SINGLE TREATMENT RESPONSE OVERALL; Overall Diameter: 1.240 INCHES MINIMUM AND 1.260 INCHES MAXIMUM IN; Hardness Rating: 34.0 ROCKWELL C MINIMUM AND 38.0 ROCKWELL C MAXIMUM. 13 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.