The Screw,cap,socket Head, cataloged under National Stock Number 5305-01-296-8619, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is American Society of Mechanical Engineers Inc. Government technical data includes 14 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 5305-01-296-8619 |
| Primary Part Number | B18.3 |
| Item Name | Screw,cap,socket Head |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | American Society of Mechanical Engineers Inc |
| Status | ACTIVE |
| Width Across Flats | 0.188 INCHES NOMINAL IN |
| Head Height | 0.244 INCHES MINIMUM IN |
| Fastener Length | 0.500 INCHES NOMINAL IN |
| Thread Length | 0.500 INCHES NOMINAL IN |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Head Style | FILLISTER |
| Thread Direction | RIGHT-HAND |
| Nondefinitive Spec/std Data | 2 TYPE |
| Internal Drive Style | HEXAGON |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 20 |
| Material | NICKEL ALLOY 400 OVERALL |
| Thread Series Designator | UNRC |
| Head Diameter | 0.365 INCHES MINIMUM IN |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
NSN 5305-01-296-8619 is a Screw,cap,socket Head, manufactured by American Society of Mechanical Engineers Inc, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-296-8619 has 2 manufacturer part numbers on file: B18.3 (American Society of Mechanical Engineers Inc), TABLE 1A (American Society of Mechanical Engineers Inc).
1 possible match (shared part number, not a government interchangeability claim): 6515-01-359-8066. Verify interchangeability with system specifications before substitution.
Key specifications for B18.3: Width Across Flats: 0.188 INCHES NOMINAL IN; Head Height: 0.244 INCHES MINIMUM IN; Fastener Length: 0.500 INCHES NOMINAL IN; Thread Length: 0.500 INCHES NOMINAL IN. 14 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.