The Screw,machine, cataloged under National Stock Number 5305-00-754-4254, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Telemechanics Inc. Government technical data includes 13 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-00-754-4254 |
| Primary Part Number | 521397778 |
| Item Name | Screw,machine |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Telemechanics Inc |
| Status | ACTIVE |
| Screw Surface Treatment | ZINC |
| Fastener Length | 0.250 INCHES NOMINAL IN |
| Thread Length | 0.219 INCHES MINIMUM IN |
| Nominal Thread Diameter | 0.099 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Screw Material | STEEL |
| Internal Drive Style | SLOT |
| Countersink Angle | 90.0 DEGREES NOMINAL |
| Thread Class | 2A A |
| Thread Quantity Per Inch | 56 |
| Thread Series Designator | UNF |
| Head Diameter | 0.188 INCHES NOMINAL 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 |
|---|---|
| 521397778 PRIMARY | Telemechanics Inc (USA) |
| Reference | Meaning |
|---|---|
| 139777 | 5/9 Secondary reference At and T Corp |
| 139777 | 5/9 Secondary reference American Telephone and Telegraph Co |
NSN 5305-00-754-4254 is a Screw,machine, manufactured by Telemechanics Inc, classified under FSC 5305, Screws. Status: active.
NSN 5305-00-754-4254 has 1 manufacturer part number on file: 521397778 (Telemechanics Inc).
1 possible match (shared part number, not a government interchangeability claim): 5920-01-645-1109. Verify interchangeability with system specifications before substitution.
Key specifications for 521397778: Screw Surface Treatment: ZINC; Fastener Length: 0.250 INCHES NOMINAL IN; Thread Length: 0.219 INCHES MINIMUM IN; Nominal Thread Diameter: 0.099 INCHES IN. 13 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.