The Washer,concave, cataloged under National Stock Number 5310-01-156-3757, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is The Boeing Company Div Defense. 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-01-156-3757 |
| Primary Part Number | 74A550696-2011 |
| Item Name | Washer,concave |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | The Boeing Company Div Defense |
| Status | ACTIVE |
| Surface Finish | 63.0 MICROINCHES BOTTOM |
| Radius | 0.690 INCHES NOMINAL IN |
| Style Designator | CONCAVE |
| Material Document and Classification | AMS 5737 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Outside Diameter | 0.840 INCHES NOMINAL IN |
| Recess Depth | 0.090 INCHES NOMINAL IN |
| Material Thickness | 0.175 INCHES MINIMUM AND 0.185 INCHES MAXIMUM IN |
| Material | IRON ALLOY 660 OVERALL |
| Hole Diameter | 0.480 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 |
|---|---|
| 74A550696-2011 PRIMARY | The Boeing Company Div Defense (USA) |
| Reference | Meaning |
|---|---|
| 74A550696-2011 | C/1 Advisory reference — outside the item-of-supply concept U.S. Government activity |
| 10130720 | 6/9 Informative reference only Nimikkeistokeskus Ncb Finland |
NSN 5310-01-156-3757 is a Washer,concave, manufactured by The Boeing Company Div Defense, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-156-3757 has 1 manufacturer part number on file: 74A550696-2011 (The Boeing Company Div Defense).
Key specifications for 74A550696-2011: Surface Finish: 63.0 MICROINCHES BOTTOM; Radius: 0.690 INCHES NOMINAL IN; Style Designator: CONCAVE; Material Document and Classification: AMS 5737 ASSN STD SINGLE MATERIAL RESPONSE 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.