The Bolt,shear, cataloged under National Stock Number 5306-00-478-9975, is classified within Federal Supply Class 5306 (Bolts) of the Hardware and Abrasives group. The manufacturer of record is Howmet Global Fastening Systems Inc. Government technical data includes 18 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through both NSN and commercial part number lookups. 6 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5306-00-478-9975 |
| Primary Part Number | VS2521-5F8 |
| Item Name | Bolt,shear |
| FSC / FSG | 5306 / 53 — Bolts |
| Manufacturer | Howmet Global Fastening Systems Inc |
| Status | ACTIVE |
| Head Height | 0.187 INCHES NOMINAL IN |
| Fastener Length | 0.835 INCHES MINIMUM AND 0.882 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | NAS 672 ASSN STD SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.325 INCHES MINIMUM AND 0.392 INCHES MAXIMUM IN |
| Hardness Rating | 46.0 ROCKWELL C MINIMUM AND 50.0 ROCKWELL C MAXIMUM OVERALL |
| Material Document and Classification | M-107 FSCM 56878 MFR REF SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.312 INCHES IN |
| Head Style | DOUBLE HEXAGON |
| Thread Direction | RIGHT-HAND |
| Grip Length | 0.490 INCHES MINIMUM AND 0.510 INCHES MAXIMUM IN |
| Width Between Flats | 0.492 INCHES MINIMUM AND 0.502 INCHES MAXIMUM IN |
| Grip Diameter | 0.3108 INCHES MINIMUM AND 0.3117 INCHES MAXIMUM IN |
| Surface Treatment | CADMIUM OVERALL |
| Minimum Tensile Strength | 220000 POUNDS PER SQUARE INCH LBS |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 24 |
| Material | STEEL OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| 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 |
|---|---|
| VS2521-5F8 | Howmet Global Fastening Systems Inc (USA) |
| Reference | Meaning |
|---|---|
| AIC220-5A8 | 5/9 Secondary reference Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company |
| EWSB22-5A8 | 5/9 Secondary reference U.S. Government activity |
| GB511B5-8 | 5/9 Secondary reference Northrop Grumman Systems Corporation |
| EWSB22-5A8 | 5/9 Secondary reference Sps Technologies, Llc Dba PB Fasteners |
| C081-5-8 | 3/2 Design control — primary reference U.S. Government activity |
| VS2521-5F8 | 5/9 Secondary reference U.S. Government activity |
NSN 5306-00-478-9975 is a Bolt,shear, manufactured by Howmet Global Fastening Systems Inc, classified under FSC 5306, Bolts. Status: active.
NSN 5306-00-478-9975 has 1 manufacturer part number on file: VS2521-5F8 (Howmet Global Fastening Systems Inc).
Key specifications for VS2521-5F8: Head Height: 0.187 INCHES NOMINAL IN; Fastener Length: 0.835 INCHES MINIMUM AND 0.882 INCHES MAXIMUM IN; Surface Treatment Document and Classification: NAS 672 ASSN STD SINGLE TREATMENT RESPONSE OVERALL; Thread Length: 0.325 INCHES MINIMUM AND 0.392 INCHES MAXIMUM IN. 18 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.