The Screw,machine, cataloged under National Stock Number 5305-01-031-3684, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Bsi Standards Limited. 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-031-3684 |
| Primary Part Number | A211-3E |
| Item Name | Screw,machine |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Bsi Standards Limited |
| Status | ACTIVE |
| Screw Surface Treatment | PASSIVATE |
| Fastener Length | 0.723 INCHES MINIMUM AND 0.753 INCHES MAXIMUM IN |
| Screw Material Document and Classification | AMS5731 ASSN STD SINGLE MATERIAL RESPONSE OR AMS5732 ASSN STD SINGLE MATERIAL RESPONSE OR AMS5737 ASSN STD SINGLE MATERIAL RESPONSE |
| Thread Length | 0.401 INCHES MINIMUM AND 0.451 INCHES MAXIMUM IN |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Specification/standard Data | 80205-NAS1221 PROFESSIONAL/INDUSTRIAL ASSOCIATION STANDARD |
| Screw Material | IRON ALLOY 660 |
| Minimum Tensile Strength | 160000 POUNDS PER SQUARE INCH LBS |
| Internal Drive Style | CROSS RECESS TYPE 1 |
| Countersink Angle | 99.0 DEGREES MINIMUM AND 101.0 DEGREES MAXIMUM |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 28 |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Head Diameter | 0.461 INCHES MINIMUM AND 0.507 INCHES MAXIMUM IN |
| Screw Surface Treatment Document and Classification | QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE |
| 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 |
|---|---|
| A211-3E PRIMARY | Bsi Standards Limited (GBR) |
| Reference | Meaning |
|---|---|
| NAS1221-4E5 | C/1 Advisory reference — outside the item-of-supply concept U.S. Government activity |
NSN 5305-01-031-3684 is a Screw,machine, manufactured by Bsi Standards Limited, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-031-3684 has 1 manufacturer part number on file: A211-3E (Bsi Standards Limited).
Key specifications for A211-3E: Screw Surface Treatment: PASSIVATE; Fastener Length: 0.723 INCHES MINIMUM AND 0.753 INCHES MAXIMUM IN; Screw Material Document and Classification: AMS5731 ASSN STD SINGLE MATERIAL RESPONSE OR AMS5732 ASSN STD SINGLE MATERIAL RESPONSE OR AMS5737 ASSN STD SINGLE MATERIAL RESPONSE; Thread Length: 0.401 INCHES MINIMUM AND 0.451 INCHES MAXIMUM IN. 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.