The Washer,concave, cataloged under National Stock Number 5310-01-646-0116, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Howmet Global Fastening Systems Inc. Government technical data includes 8 specifications, cited from the U.S. Government catalog. The record lists 3 manufacturer part numbers 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 5310-01-646-0116 |
| Primary Part Number | K39787-4 |
| Item Name | Washer,concave |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Howmet Global Fastening Systems Inc |
| Status | ACTIVE |
| Radius | 0.290 INCHES MINIMUM AND 0.310 INCHES MAXIMUM IN |
| Style Designator | CONCAVE |
| Material Document and Classification | AMS6358 ASSN STD SINGLE MATERIAL RESPONSE OR AMS6322 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Outside Diameter | 0.505 INCHES MINIMUM AND 0.515 INCHES MAXIMUM IN |
| Recess Depth | 0.054 INCHES NOMINAL IN |
| Material Thickness | 0.090 INCHES MINIMUM AND 0.115 INCHES MAXIMUM IN |
| Material | STEEL OVERALL |
| Hole Diameter | 0.335 INCHES MINIMUM AND 0.345 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 |
|---|---|
| K39787-4 PRIMARY | Howmet Global Fastening Systems Inc (USA) |
| LE153-0002-0004 | Howmet Global Fastening Systems Inc (USA) |
| LE153-0002-0004 | Sps Technologies, Llc Dba PB Fasteners (USA) |
| Reference | Meaning |
|---|---|
| LE153-0002-0004 | 5/2 Secondary reference U.S. Government activity |
| LE153-0002-0004 | 7/2 Vendor item drawing reference The Boeing Company Div Legacy Am&m |
NSN 5310-01-646-0116 is a Washer,concave, manufactured by Howmet Global Fastening Systems Inc, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-646-0116 has 3 manufacturer part numbers on file: K39787-4 (Howmet Global Fastening Systems Inc), LE153-0002-0004 (Howmet Global Fastening Systems Inc), LE153-0002-0004 (Sps Technologies, Llc Dba PB Fasteners).
Key specifications for K39787-4: Radius: 0.290 INCHES MINIMUM AND 0.310 INCHES MAXIMUM IN; Style Designator: CONCAVE; Material Document and Classification: AMS6358 ASSN STD SINGLE MATERIAL RESPONSE OR AMS6322 ASSN STD SINGLE MATERIAL RESPONSE OVERALL; Outside Diameter: 0.505 INCHES MINIMUM AND 0.515 INCHES MAXIMUM IN. 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.