The Bolt,machine, cataloged under National Stock Number 5306-00-439-8557, is classified within Federal Supply Class 5306 (Bolts) of the Hardware and Abrasives group. The manufacturer of record is Rtx Corporation Dba Pratt & Whitney Div Pratt &whitney. Government technical data includes 14 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. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5306-00-439-8557 |
| Primary Part Number | 126375 |
| Item Name | Bolt,machine |
| FSC / FSG | 5306 / 53 — Bolts |
| Manufacturer | Rtx Corporation Dba Pratt & Whitney Div Pratt &whitney |
| Status | ACTIVE |
| Head Height | 0.280 INCHES NOMINAL IN |
| Fastener Length | 0.550 INCHES MINIMUM AND 0.570 INCHES MAXIMUM IN |
| Thread Length | 0.470 INCHES MINIMUM IN |
| Material Document and Classification | MIL-S-5626 MIL SPEC 1ST MATERIAL RESPONSE OR MIL-S-5000 MIL SPEC 2ND MATERIAL RESPONSE OR MIL-S-8503 MIL SPEC 3RD MATERIAL RESPONSE OR MIL-S-6098 MIL SPEC 4TH MATERIAL RESPONSE OR MIL-S-6049 MIL SPEC 5TH MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.312 INCHES IN |
| Features Provided | FINISHED HEAD |
| Head Style | HEXAGON |
| Thread Direction | RIGHT-HAND |
| Grip Length | 0.080 INCHES MINIMUM AND 0.100 INCHES MAXIMUM IN |
| Width Between Flats | 0.500 INCHES NOMINAL IN |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 24 |
| Material | STEEL COMP 4140 OR STEEL COMP E4340 OR STEEL COMP 6150 OR STEEL COMP 8735 OR STEEL COMP 8740 OVERALL |
| Thread Series Designator | UNF |
| 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 |
|---|---|
| 126375 PRIMARY | Rtx Corporation Dba Pratt & Whitney Div Pratt &whitney (USA) |
NSN 5306-00-439-8557 is a Bolt,machine, manufactured by Rtx Corporation Dba Pratt & Whitney Div Pratt &whitney, classified under FSC 5306, Bolts. Status: active.
NSN 5306-00-439-8557 has 1 manufacturer part number on file: 126375 (Rtx Corporation Dba Pratt & Whitney Div Pratt &whitney).
2 possible matches (shared part number, not a government interchangeability claim): 5310-01-127-7103, 6680-01-326-8855. Verify interchangeability with system specifications before substitution.
Key specifications for 126375: Head Height: 0.280 INCHES NOMINAL IN; Fastener Length: 0.550 INCHES MINIMUM AND 0.570 INCHES MAXIMUM IN; Thread Length: 0.470 INCHES MINIMUM IN; Material Document and Classification: MIL-S-5626 MIL SPEC 1ST MATERIAL RESPONSE OR MIL-S-5000 MIL SPEC 2ND MATERIAL RESPONSE OR MIL-S-8503 MIL SPEC 3RD MATERIAL RESPONSE OR MIL-S-6098 MIL SPEC 4TH MATERIAL RESPONSE OR MIL-S-6049 MIL SPEC 5TH MATERIAL RESPONSE OVERALL. 14 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.