The Screw,close Tolerance, cataloged under National Stock Number 5305-01-042-6317, 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 1 manufacturer part number 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through both NSN and commercial part number lookups. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 5305-01-042-6317 |
| Primary Part Number | HT8138-3-19T |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Howmet Global Fastening Systems Inc |
| Status | ACTIVE |
| Surface Finish | 32.0 MICROINCHES THREADS |
| Surface Finish | 32.0 MICROINCHES GRIP |
| Fastener Length | 1.511 INCHES MINIMUM AND 1.558 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | QQ-P-416,TYPE 2,CLASS 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.313 INCHES MINIMUM AND 0.380 INCHES MAXIMUM IN |
| Hardness Rating | 36.0 ROCKWELL C MINIMUM AND 40.0 ROCKWELL C MAXIMUM OVERALL |
| Shank Unthreaded Hole Diameter | 0.070 INCHES MINIMUM AND 0.080 INCHES MAXIMUM FIRST HOLE IN |
| Nominal Thread Diameter | 0.190 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Grip Length | 1.178 INCHES MINIMUM AND 1.198 INCHES MAXIMUM IN |
| Grip Diameter | 0.1885 INCHES MINIMUM AND 0.1895 INCHES MAXIMUM IN |
| Surface Treatment | CADMIUM AND CHROMATE OVERALL |
| Internal Drive Style | HIGH-TORQUE |
| Countersink Angle | 100.0 DEGREES NOMINAL |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 32 |
| 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 |
| Distance From Head Largest Bearing Surface to Shank Hole Center | 0.153 INCHES MINIMUM AND 0.173 INCHES MAXIMUM FIRST HOLE IN |
| Head Diameter | 0.350 INCHES MINIMUM AND 0.381 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 |
|---|---|
| HT8138-3-19T PRIMARY | Howmet Global Fastening Systems Inc (USA) |
| Reference | Meaning |
|---|---|
| GB510AE3-19T | 7/2 Vendor item drawing reference Northrop Grumman Systems Corporation |
| 106712-3-19T | 5/2 Secondary reference U.S. Government activity |
| BM19051-3-19T | C/1 Advisory reference — outside the item-of-supply concept U.S. Government activity |
| HT8138-3-19T | 5/9 Secondary reference U.S. Government activity |
NSN 5305-01-042-6317 is a Screw,close Tolerance, manufactured by Howmet Global Fastening Systems Inc, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-042-6317 has 1 manufacturer part number on file: HT8138-3-19T (Howmet Global Fastening Systems Inc).
Key specifications for HT8138-3-19T: Surface Finish: 32.0 MICROINCHES THREADS; Surface Finish: 32.0 MICROINCHES GRIP; Fastener Length: 1.511 INCHES MINIMUM AND 1.558 INCHES MAXIMUM IN; Surface Treatment Document and Classification: QQ-P-416,TYPE 2,CLASS 3 FED SPEC SINGLE TREATMENT RESPONSE 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.