The Screw,cap,socket Head, cataloged under National Stock Number 5305-01-306-7873, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Mcmaster-Carr Supply Co. Government technical data includes 18 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. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-306-7873 |
| Primary Part Number | 91251A626 |
| Item Name | Screw,cap,socket Head |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Mcmaster-Carr Supply Co |
| Status | ACTIVE |
| Width Across Flats | 0.312 INCHES NOMINAL IN |
| Head Height | 0.368 INCHES MINIMUM AND 0.375 INCHES MAXIMUM IN |
| Fastener Length | 1.250 INCHES NOMINAL IN |
| Thread Length | 1.125 INCHES MINIMUM AND 1.250 INCHES MAXIMUM IN |
| Hardness Rating | 39.0 ROCKWELL C MINIMUM AND 45.0 ROCKWELL C MAXIMUM OVERALL |
| Material Document and Classification | SAE GRADE 8 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.375 INCHES IN |
| Head Style | KNURLED NO. 1 |
| Thread Direction | RIGHT-HAND |
| Color | BLACK OVERALL |
| Surface Treatment | OXIDE OVERALL |
| Minimum Tensile Strength | 180000 POUNDS PER SQUARE INCH LBS |
| Internal Drive Style | HEXAGON |
| Thread Class | 2A A |
| Thread Quantity Per Inch | 16 |
| Material | STEEL OVERALL |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) |
| Head Diameter | 0.550 INCHES MINIMUM AND 0.562 INCHES MAXIMUM IN |
| 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 |
|---|---|
| A0440240116K | Suburban Bolt & Supply Co (USA) |
| 91251A626 PRIMARY | Mcmaster-Carr Supply Co (USA) |
| 91251A626 PRIMARY | Mcmaster-Carr Supply Co (USA) |
NSN 5305-01-306-7873 is a Screw,cap,socket Head, manufactured by Mcmaster-Carr Supply Co, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-306-7873 has 3 manufacturer part numbers on file: A0440240116K (Suburban Bolt & Supply Co), 91251A626 (Mcmaster-Carr Supply Co), 91251A626 (Mcmaster-Carr Supply Co).
Key specifications for 91251A626: Width Across Flats: 0.312 INCHES NOMINAL IN; Head Height: 0.368 INCHES MINIMUM AND 0.375 INCHES MAXIMUM IN; Fastener Length: 1.250 INCHES NOMINAL IN; Thread Length: 1.125 INCHES MINIMUM AND 1.250 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.