The Bolt,machine, cataloged under National Stock Number 5306-01-497-4197, is classified within Federal Supply Class 5306 (Bolts) of the Hardware and Abrasives group. The manufacturer of record is Rolls Royce Corp. Government technical data includes 12 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. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5306-01-497-4197 |
| Primary Part Number | MS9491-20 |
| Item Name | Bolt,machine |
| FSC / FSG | 5306 / 53 — Bolts |
| Manufacturer | Rolls Royce Corp |
| Status | ACTIVE |
| Head Height | 0.188 INCHES NOMINAL IN |
| Fastener Length | 1.500 INCHES NOMINAL IN |
| Thread Length | 0.875 INCHES MINIMUM AND 0.935 INCHES MAXIMUM IN |
| Material Document and Classification | AMS 5731 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.312 INCHES IN |
| Head Style | HEXAGON |
| Thread Direction | RIGHT-HAND |
| Width Between Flats | 0.492 INCHES MINIMUM AND 0.502 INCHES MAXIMUM IN |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 24 |
| Material | IRON ALLOY 660 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 |
|---|---|
| MS9491-20 PRIMARY | Rolls Royce Corp (USA) |
NSN 5306-01-497-4197 is a Bolt,machine, manufactured by Rolls Royce Corp, classified under FSC 5306, Bolts. Status: active.
NSN 5306-01-497-4197 has 1 manufacturer part number on file: MS9491-20 (Rolls Royce Corp).
Key specifications for MS9491-20: Head Height: 0.188 INCHES NOMINAL IN; Fastener Length: 1.500 INCHES NOMINAL IN; Thread Length: 0.875 INCHES MINIMUM AND 0.935 INCHES MAXIMUM IN; Material Document and Classification: AMS 5731 ASSN STD SINGLE MATERIAL RESPONSE OVERALL. 12 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.