The Screw,machine, cataloged under National Stock Number 5305-01-307-4389, 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 11 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-307-4389 |
| Primary Part Number | 91781A078 |
| Item Name | Screw,machine |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Mcmaster-Carr Supply Co |
| Status | ACTIVE |
| Fastener Length | 0.312 INCHES NOMINAL IN |
| Nominal Thread Diameter | 0.086 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Nondefinitive Spec/std Data | 1 TYPE AND 2S STYLE |
| Screw Material | STEEL CORROSION RESISTING |
| Internal Drive Style | SLOT |
| Countersink Angle | 82.0 DEGREES NOMINAL |
| Thread Class | 2A A |
| Thread Quantity Per Inch | 56 |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) |
| 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 |
|---|---|
| 91781A078 | Mcmaster-Carr Supply Co (USA) |
| Reference | Meaning |
|---|---|
| 91783A078 | 5/9 Secondary reference Mcmaster-Carr Supply Co |
| FF-S-72 | 4/1 Identification reference U.S. Government activity |
| 91910A078 | 5/9 Secondary reference Mcmaster-Carr Supply Co |
NSN 5305-01-307-4389 is a Screw,machine, manufactured by Mcmaster-Carr Supply Co, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-307-4389 has 1 manufacturer part number on file: 91781A078 (Mcmaster-Carr Supply Co).
Key specifications for 91781A078: Fastener Length: 0.312 INCHES NOMINAL IN; Nominal Thread Diameter: 0.086 INCHES IN; Head Style: FLAT COUNTERSUNK; Thread Direction: RIGHT-HAND. 11 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.