The Bolt,externally Relieved Body, cataloged under National Stock Number 5306-00-526-4076, is classified within Federal Supply Class 5306 (Bolts) of the Hardware and Abrasives group. The manufacturer of record is Rtx Corporation Div Pratt & Whitney. Government technical data includes 26 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5306-00-526-4076 |
| Primary Part Number | 4044389 |
| Item Name | Bolt,externally Relieved Body |
| FSC / FSG | 5306 / 53 — Bolts |
| Manufacturer | Rtx Corporation Div Pratt & Whitney |
| Status | ACTIVE |
| Fourth Diameter From Head | 0.165 INCHES MINIMUM AND 0.175 INCHES MAXIMUM IN |
| Extended Washer Thickness | 0.060 INCHES MINIMUM IN |
| Head Height | 0.293 INCHES MINIMUM AND 0.313 INCHES MAXIMUM IN |
| Fastener Length | 1.005 INCHES MINIMUM AND 1.025 INCHES MAXIMUM IN |
| Extended Washer Diameter | 0.428 INCHES MINIMUM AND 0.448 INCHES MAXIMUM IN |
| Thread Length | 0.455 INCHES MINIMUM AND 0.595 INCHES MAXIMUM IN |
| Hardness Rating | 34.0 ROCKWELL C MINIMUM AND 44.0 ROCKWELL C MAXIMUM OVERALL |
| Material Document and Classification | AMS 5708 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| First Diameter From Head | 0.250 INCHES MINIMUM AND 0.252 INCHES MAXIMUM IN |
| Distance From Largest Bearing Surface of Head to End of Second Diameter | 0.310 INCHES MINIMUM AND 0.320 INCHES MAXIMUM IN |
| Nominal Thread Diameter | 0.190 INCHES IN |
| Distance From Largest Bearing Surface of Head to End of Third Diameter | 0.360 INCHES MINIMUM AND 0.370 INCHES MAXIMUM IN |
| Head Style | DOUBLE HEXAGON W/HOLE |
| Thread Direction | RIGHT-HAND |
| Second Diameter From Head | 0.185 INCHES MINIMUM AND 0.195 INCHES MAXIMUM IN |
| Width Between Flats | 0.312 INCHES NOMINAL IN |
| Distance From Largest Bearing Surface of Head to End of First Diameter | 0.205 INCHES MINIMUM AND 0.225 INCHES MAXIMUM IN |
| Externally Relieved Body Diameter Quantity | 4 |
| Minimum Tensile Strength | 175000 POUNDS PER SQUARE INCH LBS |
| Minimum Yield Strength | 115000 POUNDS PER SQUARE INCH LBS |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 32 |
| Material | NICKEL ALLOY OVERALL |
| Distance From Largest Bearing Surface of Head to End of Fourth Diameter | 0.430 INCHES MINIMUM AND 0.550 INCHES MAXIMUM IN |
| Third Diameter From Head | 0.250 INCHES MINIMUM AND 0.252 INCHES MAXIMUM IN |
| 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 | F |
| Part Number | Manufacturer |
|---|---|
| 4044389 | M.s. Aerospace Inc. Dba Ms Aerospace Inc (USA) |
| 4044389 PRIMARY | Rtx Corporation Div Pratt & Whitney (USA) |
| Reference | Meaning |
|---|---|
| 4044389 | 5/9 Secondary reference Necchi Spa |
| 4044389 | 5/9 Secondary reference Sps Technologies, Llc Dba PB Fasteners |
| 4044389 | 5/9 Secondary reference Rtx Corporation Dba Pratt & Whitney Div Pratt &whitney |
| 4044389 | 5/9 Secondary reference Turbo Power & Marine System Inc Sub of United Technologies Corp |
NSN 5306-00-526-4076 is a Bolt,externally Relieved Body, manufactured by Rtx Corporation Div Pratt & Whitney, classified under FSC 5306, Bolts. Status: active.
NSN 5306-00-526-4076 has 2 manufacturer part numbers on file: 4044389 (M.s. Aerospace Inc. Dba Ms Aerospace Inc), 4044389 (Rtx Corporation Div Pratt & Whitney).
Key specifications for 4044389: Fourth Diameter From Head: 0.165 INCHES MINIMUM AND 0.175 INCHES MAXIMUM IN; Extended Washer Thickness: 0.060 INCHES MINIMUM IN; Head Height: 0.293 INCHES MINIMUM AND 0.313 INCHES MAXIMUM IN; Fastener Length: 1.005 INCHES MINIMUM AND 1.025 INCHES MAXIMUM IN. 26 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.