The Screw,close Tolerance, cataloged under National Stock Number 5305-01-090-6337, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company. Government technical data includes 17 specifications, cited from the U.S. Government catalog. The record lists 6 manufacturer part numbers 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 5305-01-090-6337 |
| Primary Part Number | BACB30LR4-21 |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company |
| Status | ACTIVE |
| Fastener Length | 1.722 INCHES MINIMUM AND 1.752 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | QQ-P-416 TY 2 CL 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.400 INCHES MINIMUM AND 0.450 INCHES MAXIMUM IN |
| Material Document and Classification | AMS 5737 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Grip Length | 1.302 INCHES MINIMUM AND 1.322 INCHES MAXIMUM IN |
| Grip Diameter | 0.2485 INCHES MINIMUM AND 0.2495 INCHES MAXIMUM IN |
| Surface Treatment | CADMIUM AND CHROMATE OVERALL |
| 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 |
| Material | IRON ALLOY 660 OVERALL |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Head Diameter | 0.455 INCHES MINIMUM AND 0.510 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 |
|---|---|
| BACB30LR4-21 | Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company (USA) |
| BACB30LR4-21 | Federal Manufacturing Corp (USA) |
| BACB30LR4-21 | Valley-Todeco, Inc. Dba Arconic Fastening Systems (USA) |
| BACB30LR4-21 | Howmet Global Fastening Systems Inc Div City of Industry Operations (USA) |
| BACB30LR4-21 | Sps Technologies Llc Dba PB Fasteners Div PB Fasteners (USA) |
| BACB30LR4-21 | Sps Technologies, Llc Dba PB Fasteners (USA) |
| Reference | Meaning |
|---|---|
| BACB30LR4-21 | 5/9 Secondary reference Huck International, Inc |
| BACB30LR4-21 | 5/9 Secondary reference U.S. Government activity |
| BACB30LR4-21 | 3/2 Design control — primary reference U.S. Government activity |
NSN 5305-01-090-6337 is a Screw,close Tolerance, manufactured by Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-090-6337 has 6 manufacturer part numbers on file: BACB30LR4-21 (Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company), BACB30LR4-21 (Federal Manufacturing Corp), BACB30LR4-21 (Valley-Todeco, Inc. Dba Arconic Fastening Systems), BACB30LR4-21 (Howmet Global Fastening Systems Inc Div City of Industry Operations), BACB30LR4-21 (Sps Technologies Llc Dba PB Fasteners Div PB Fasteners) and 1 more.
Key specifications for BACB30LR4-21: Fastener Length: 1.722 INCHES MINIMUM AND 1.752 INCHES MAXIMUM IN; Surface Treatment Document and Classification: QQ-P-416 TY 2 CL 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Thread Length: 0.400 INCHES MINIMUM AND 0.450 INCHES MAXIMUM IN; Material Document and Classification: AMS 5737 ASSN STD SINGLE MATERIAL RESPONSE 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.