The Screw,close Tolerance, cataloged under National Stock Number 5305-01-050-9652, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Sps Technologies Llc Dba PB Fasteners Div PB Fasteners. Government technical data includes 15 specifications, cited from the U.S. Government catalog. The record lists 4 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 5305-01-050-9652 |
| Primary Part Number | BACB3OLR4U21 |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Sps Technologies Llc Dba PB Fasteners Div PB Fasteners |
| Status | ACTIVE |
| Fastener Length | 1.722 INCHES MINIMUM AND 1.752 INCHES MAXIMUM IN |
| Thread Length | 0.400 INCHES MINIMUM AND 0.450 INCHES MAXIMUM IN |
| 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 | 0.2490 INCHES MINIMUM AND 0.2495 INCHES MAXIMUM IN |
| Surface Treatment | PASSIVATE OVERALL |
| Internal Drive Style | CROSS RECESS TYPE 1 |
| Countersink Angle | 100.0 DEGREES NOMINAL |
| 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 |
|---|---|
| BACB3OLR4U21 | Sps Technologies Llc Dba PB Fasteners Div PB Fasteners (USA) |
| BACB30LR4U21 | Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company (USA) |
| BACB3OLR4U21 | Valley-Todeco, Inc. Dba Arconic Fastening Systems (USA) |
| BACB3OLR4U21 | Federal Manufacturing Corp (USA) |
| Reference | Meaning |
|---|---|
| BACB30LR4U21 | 3/2 Design control — primary reference U.S. Government activity |
| BACB3OLR4U21 | 5/9 Secondary reference Voi-Shan/chatsworth Div of Vsi Corp Sub of Fairchild Industries Inc |
| BACB3OLR4U21 | 5/2 Secondary reference U.S. Government activity |
NSN 5305-01-050-9652 is a Screw,close Tolerance, manufactured by Sps Technologies Llc Dba PB Fasteners Div PB Fasteners, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-050-9652 has 4 manufacturer part numbers on file: BACB3OLR4U21 (Sps Technologies Llc Dba PB Fasteners Div PB Fasteners), BACB30LR4U21 (Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company), BACB3OLR4U21 (Valley-Todeco, Inc. Dba Arconic Fastening Systems), BACB3OLR4U21 (Federal Manufacturing Corp).
Key specifications for BACB3OLR4U21: Fastener Length: 1.722 INCHES MINIMUM AND 1.752 INCHES MAXIMUM IN; Thread Length: 0.400 INCHES MINIMUM AND 0.450 INCHES MAXIMUM IN; Nominal Thread Diameter: 0.250 INCHES IN; Head Style: FLAT COUNTERSUNK. 15 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.