The Screw,cap,socket Head, cataloged under National Stock Number 5305-00-977-8978, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Long-Lok, Llc. Government technical data includes 17 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-00-977-8978 |
| Primary Part Number | LL24667-7 |
| Item Name | Screw,cap,socket Head |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Long-Lok, Llc |
| Status | ACTIVE |
| Width Across Flats | 0.078 INCHES NOMINAL IN |
| Fastener Length | 0.250 INCHES NOMINAL IN |
| Thread Length | 0.250 INCHES MAXIMUM IN |
| Hardness Rating | 36.0 ROCKWELL C MINIMUM AND 43.0 ROCKWELL C MAXIMUM OVERALL |
| Material Document and Classification | 66 FED STD SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.138 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Locking Feature | STRIP THREADS |
| Surface Treatment | CADMIUM AND CHROMATE OVERALL |
| Internal Drive Style | HEXAGON |
| Countersink Angle | 80.0 DEGREES MINIMUM AND 82.0 DEGREES MAXIMUM |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 32 |
| Material | STEEL OVERALL |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) |
| Head Diameter | 0.255 INCHES MINIMUM AND 0.271 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 |
|---|---|
| LL24667-7 | Long-Lok, Llc (USA) |
| Reference | Meaning |
|---|---|
| 250514 | 3/2 Design control — primary reference U.S. Government activity |
NSN 5305-00-977-8978 is a Screw,cap,socket Head, manufactured by Long-Lok, Llc, classified under FSC 5305, Screws. Status: active.
NSN 5305-00-977-8978 has 1 manufacturer part number on file: LL24667-7 (Long-Lok, Llc).
2 possible matches (shared part number, not a government interchangeability claim): 5965-01-079-7936, 4820-01-267-0433. Verify interchangeability with system specifications before substitution.
Key specifications for LL24667-7: Width Across Flats: 0.078 INCHES NOMINAL IN; Fastener Length: 0.250 INCHES NOMINAL IN; Thread Length: 0.250 INCHES MAXIMUM IN; Hardness Rating: 36.0 ROCKWELL C MINIMUM AND 43.0 ROCKWELL C MAXIMUM OVERALL. 17 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.