The Washer,concave, cataloged under National Stock Number 5310-01-322-3556, 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 10 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-01-322-3556 |
| Primary Part Number | KFN619B5 |
| Item Name | Washer,concave |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Howmet Global Fastening Systems Inc |
| Status | ACTIVE |
| Surface Treatment Document and Classification | QQ-P-416,TY 2,CL 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Radius | 0.180 INCHES MINIMUM AND 0.185 INCHES MAXIMUM IN |
| Style Designator | CONCAVE |
| Material Document and Classification | AMS 5643,COND H-1025 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Outside Diameter | 0.325 INCHES MINIMUM AND 0.335 INCHES MAXIMUM IN |
| Recess Depth | 0.035 INCHES NOMINAL IN |
| Material Thickness | 0.085 INCHES MINIMUM AND 0.095 INCHES MAXIMUM IN |
| Surface Treatment | CADMIUM AND CHROMATE OVERALL |
| Material | STEEL COMP 630 OVERALL |
| Hole Diameter | 0.235 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 |
NSN 5310-01-322-3556 is a Washer,concave, manufactured by Howmet Global Fastening Systems Inc, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-322-3556 has 3 manufacturer part numbers on file: KFN619B5 (Sps Technologies, Llc Dba PB Fasteners), KFN619B5 (Howmet Global Fastening Systems Inc), KFN619B5 (Huck International, Inc).
Key specifications for KFN619B5: Surface Treatment Document and Classification: QQ-P-416,TY 2,CL 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Radius: 0.180 INCHES MINIMUM AND 0.185 INCHES MAXIMUM IN; Style Designator: CONCAVE; Material Document and Classification: AMS 5643,COND H-1025 ASSN STD SINGLE MATERIAL RESPONSE OVERALL. 10 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.