The Bolt,externally Relieved Body, cataloged under National Stock Number 5306-01-080-0677, is classified within Federal Supply Class 5306 (Bolts) of the Hardware and Abrasives group. The manufacturer of record is Hensoldt Sensors Gmbh. Government technical data includes 19 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 5306-01-080-0677 |
| Primary Part Number | 321921-1 |
| Item Name | Bolt,externally Relieved Body |
| FSC / FSG | 5306 / 53 — Bolts |
| Manufacturer | Hensoldt Sensors Gmbh |
| Status | ACTIVE |
| Head Height | 0.250 INCHES NOMINAL IN |
| Fastener Length | 1.750 INCHES NOMINAL IN |
| Surface Treatment Document and Classification | QQ-P-35 TYPE I FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.547 INCHES NOMINAL IN |
| Material Document and Classification | AMS 5643 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| First Diameter From Head | 0.220 INCHES NOMINAL IN |
| Distance From Largest Bearing Surface of Head to End of Second Diameter | 1.203 INCHES NOMINAL IN |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Head Style | HEXAGON |
| Thread Direction | RIGHT-HAND |
| Second Diameter From Head | 0.177 INCHES MINIMUM AND 0.187 INCHES MAXIMUM IN |
| Width Between Flats | 0.438 INCHES NOMINAL IN |
| Distance From Largest Bearing Surface of Head to End of First Diameter | 0.250 INCHES NOMINAL IN |
| Externally Relieved Body Diameter Quantity | 2 |
| Surface Treatment | PASSIVATE OVERALL |
| Thread Class | 2A A |
| Thread Quantity Per Inch | 20 |
| Material | STEEL CORROSION RESISTING OVERALL |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) |
| 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 |
|---|---|
| 321921-1 | Hensoldt Sensors Gmbh (DEU) |
| 321921-1 | Leonardo Mw Ltd (GBR) |
| 321921-1 | Leonardo S.p.a. Div Electronics (ITA) |
| Reference | Meaning |
|---|---|
| 321921-1 | 3/2 Design control — primary reference U.S. Government activity |
| 321921-1 | 5/9 Secondary reference Fiar Fabbrica Italiana Apparecchiature Radioelettriche Spa |
NSN 5306-01-080-0677 is a Bolt,externally Relieved Body, manufactured by Hensoldt Sensors Gmbh, classified under FSC 5306, Bolts. Status: active.
NSN 5306-01-080-0677 has 3 manufacturer part numbers on file: 321921-1 (Hensoldt Sensors Gmbh), 321921-1 (Leonardo Mw Ltd), 321921-1 (Leonardo S.p.a. Div Electronics).
Key specifications for 321921-1: Head Height: 0.250 INCHES NOMINAL IN; Fastener Length: 1.750 INCHES NOMINAL IN; Surface Treatment Document and Classification: QQ-P-35 TYPE I FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Thread Length: 0.547 INCHES NOMINAL IN. 19 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.