The Screw,close Tolerance, cataloged under National Stock Number 5305-01-134-8728, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Howmet Global Fastening Systems Inc. Government technical data includes 21 specifications, cited from the U.S. Government catalog. The record lists 5 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-134-8728 |
| Primary Part Number | 79901HD-4-12 |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Howmet Global Fastening Systems Inc |
| Status | ACTIVE |
| Fastener Length | 1.111 INCHES MINIMUM AND 1.158 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | MIL-C-8837 TYPE 2 CLASS 2 MIL SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.351 INCHES MINIMUM AND 0.418 INCHES MAXIMUM IN |
| Hardness Rating | 51.0 ROCKWELL C MINIMUM AND 54.0 ROCKWELL C MAXIMUM OVERALL |
| Shank Unthreaded Hole Diameter | 0.071 INCHES MINIMUM AND 0.081 INCHES MAXIMUM FIRST HOLE IN |
| Material Document and Classification | AMS6487 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Grip Length | 0.740 INCHES MINIMUM AND 0.760 INCHES MAXIMUM IN |
| Grip Diameter | 0.2483 INCHES MINIMUM AND 0.2492 INCHES MAXIMUM IN |
| Surface Treatment | CADMIUM AND CHROMATE OVERALL |
| Minimum Tensile Strength | 260000 POUNDS PER SQUARE INCH LBS |
| Internal Drive Style | HIGH-TORQUE |
| Countersink Angle | 99.0 DEGREES MINIMUM AND 101.0 DEGREES MAXIMUM |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 28 |
| Material | STEEL COMP H11 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Distance From Head Largest Bearing Surface to Shank Hole Center | 0.943 INCHES MINIMUM AND 0.975 INCHES MAXIMUM FIRST HOLE IN |
| Head Diameter | 0.447 INCHES MINIMUM AND 0.507 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 |
|---|---|
| 79901HD-4-12 PRIMARY | Howmet Global Fastening Systems Inc (USA) |
| 79901HD-4-12 PRIMARY | Hi-Shear Corporation (USA) |
| 79901HD-4-12 PRIMARY | Sps Technologies Llc Dba PB Fasteners Div PB Fasteners (USA) |
| 79901HD-4-12 PRIMARY | Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc (CAN) |
| 79901HD-4-12 PRIMARY | Sps Technologies, Llc Dba PB Fasteners (USA) |
| Reference | Meaning |
|---|---|
| GB510CS4HD12 | 5/9 Secondary reference Northrop Grumman Systems Corporation |
| 79901HD-4-12 | 3/2 Design control — primary reference U.S. Government activity |
| GB510DE412D | 7/2 Vendor item drawing reference Northrop Grumman Systems Corporation |
NSN 5305-01-134-8728 is a Screw,close Tolerance, manufactured by Howmet Global Fastening Systems Inc, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-134-8728 has 5 manufacturer part numbers on file: 79901HD-4-12 (Howmet Global Fastening Systems Inc), 79901HD-4-12 (Hi-Shear Corporation), 79901HD-4-12 (Sps Technologies Llc Dba PB Fasteners Div PB Fasteners), 79901HD-4-12 (Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc), 79901HD-4-12 (Sps Technologies, Llc Dba PB Fasteners).
Key specifications for 79901HD-4-12: Fastener Length: 1.111 INCHES MINIMUM AND 1.158 INCHES MAXIMUM IN; Surface Treatment Document and Classification: MIL-C-8837 TYPE 2 CLASS 2 MIL SPEC SINGLE TREATMENT RESPONSE OVERALL; Thread Length: 0.351 INCHES MINIMUM AND 0.418 INCHES MAXIMUM IN; Hardness Rating: 51.0 ROCKWELL C MINIMUM AND 54.0 ROCKWELL C MAXIMUM OVERALL. 21 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.