The Washer,flat, cataloged under National Stock Number 5310-01-242-7356, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Ontic Engineering & Manufacturing, Inc Dba Ontic Us. Government technical data includes 8 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-01-242-7356 |
| Primary Part Number | 99409 |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Ontic Engineering & Manufacturing, Inc Dba Ontic Us |
| Status | ACTIVE |
| Overall Diameter | 0.560 INCHES NOMINAL IN |
| Material Document and Classification | QQ-A-355,TEMPER T3 FED SPEC 1ST MATERIAL RESPONSE AND QQ-A-355TEMPER T4 FED SPEC 2ND MATERIAL RESPONSE OVERALL |
| Cross-Sectional Shape Style | RECTANGULAR |
| Peripheral Shape Style | ROUND |
| Material | ALUMINUM ALLOY OVERALL |
| Center Hole Shape Style | ROUND |
| Hole Diameter | 0.205 INCHES NOMINAL IN |
| Thickness | 0.035 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 |
|---|---|
| 99409 PRIMARY | Ontic Engineering & Manufacturing, Inc Dba Ontic Us (USA) |
| Reference | Meaning |
|---|---|
| 99409 | 5/9 Secondary reference Hamilton Sundstrand Corporation Dba Collins Aerospace |
NSN 5310-01-242-7356 is a Washer,flat, manufactured by Ontic Engineering & Manufacturing, Inc Dba Ontic Us, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-242-7356 has 1 manufacturer part number on file: 99409 (Ontic Engineering & Manufacturing, Inc Dba Ontic Us).
Key specifications for 99409: Overall Diameter: 0.560 INCHES NOMINAL IN; Material Document and Classification: QQ-A-355,TEMPER T3 FED SPEC 1ST MATERIAL RESPONSE AND QQ-A-355TEMPER T4 FED SPEC 2ND MATERIAL RESPONSE OVERALL; Cross-Sectional Shape Style: RECTANGULAR; 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.