The Bolt,close Tolerance, cataloged under National Stock Number 5306-01-520-8719, is classified within Federal Supply Class 5306 (Bolts) of the Hardware and Abrasives group. The manufacturer of record is Sps Technologies Llc Dba PB Fasteners Div PB Fasteners. Government technical data includes 22 specifications, cited from the U.S. Government catalog. The record lists 9 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5306-01-520-8719 |
| Primary Part Number | BACB30US6K21 |
| Item Name | Bolt,close Tolerance |
| FSC / FSG | 5306 / 53 — Bolts |
| Manufacturer | Sps Technologies Llc Dba PB Fasteners Div PB Fasteners |
| Status | ACTIVE |
| Extended Washer Thickness | 0.091 INCHES NOMINAL IN |
| Head Height | 0.340 INCHES NOMINAL IN |
| Fastener Length | 1.9555 INCHES NOMINAL IN |
| Extended Washer Diameter | 0.490 INCHES MINIMUM AND 0.507 INCHES MAXIMUM IN |
| Thread Length | 0.643 INCHES NOMINAL IN |
| Hole Configuration Style | DOUBLE HEXAGON LONGITUDINAL HOLE |
| Material Document and Classification | AMS5662 ASSN STD SINGLE MATERIAL RESPONSE OR AMS5962 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.375 INCHES IN |
| Head Style | DOUBLE HEXAGON W/HOLE |
| Thread Direction | RIGHT-HAND |
| Grip Length | 1.3125 INCHES NOMINAL IN |
| Width Between Flats | 0.490 INCHES MINIMUM AND 0.507 INCHES MAXIMUM IN |
| Grip Diameter | 0.3735 INCHES MINIMUM AND 0.3745 INCHES MAXIMUM IN |
| Color | BLACK THREADS |
| Surface Treatment | ALUMINUM OVERALL |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 24 |
| Material | NICKEL ALLOY 718 OVERALL |
| Hole Quantity | 1 |
| Thread Series Designator | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Hole Type | DRILLED |
| Hole Diameter | 0.260 INCHES NOMINAL 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 |
|---|---|
| BACB30US6K21 | Sps Technologies Llc Dba PB Fasteners Div PB Fasteners (USA) |
| BACB30US6K21 | Sonic Industries, Inc. Dba Sonic Industries Inc Div Sonic Industries (USA) |
| BACB30US6K21 | Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company (USA) |
| BACB30US6K21 | Howmet Global Fastening Systems Inc Div City of Industry Operations (USA) |
| BACB30US6K21 | Space-Lok, Inc. Dba Space-Lok Inc Div Space-Lok (USA) |
| BACB30US6K21 | Federal Manufacturing Corp (USA) |
| BACB30US6K21 | Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc (CAN) |
| BACB30US6K21 | Sps Technologies, Llc Dba PB Fasteners (USA) |
| BACB30US6K21 | Valley-Todeco, Inc. Dba Arconic Fastening Systems (USA) |
| Reference | Meaning |
|---|---|
| BACB30US6K21 | 3/2 Design control — primary reference U.S. Government activity |
NSN 5306-01-520-8719 is a Bolt,close Tolerance, manufactured by Sps Technologies Llc Dba PB Fasteners Div PB Fasteners, classified under FSC 5306, Bolts. Status: active.
NSN 5306-01-520-8719 has 9 manufacturer part numbers on file: BACB30US6K21 (Sps Technologies Llc Dba PB Fasteners Div PB Fasteners), BACB30US6K21 (Sonic Industries, Inc. Dba Sonic Industries Inc Div Sonic Industries), BACB30US6K21 (Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company), BACB30US6K21 (Howmet Global Fastening Systems Inc Div City of Industry Operations), BACB30US6K21 (Space-Lok, Inc. Dba Space-Lok Inc Div Space-Lok) and 4 more.
Key specifications for BACB30US6K21: Extended Washer Thickness: 0.091 INCHES NOMINAL IN; Head Height: 0.340 INCHES NOMINAL IN; Fastener Length: 1.9555 INCHES NOMINAL IN; Extended Washer Diameter: 0.490 INCHES MINIMUM AND 0.507 INCHES MAXIMUM IN. 22 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.