The Screw,close Tolerance, cataloged under National Stock Number 5305-00-810-1266, 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 19 specifications, cited from the U.S. Government catalog. The record lists 5 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-00-810-1266 |
| Primary Part Number | 51B334-40H |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Sps Technologies Llc Dba PB Fasteners Div PB Fasteners |
| Status | ACTIVE |
| Fastener Length | 2.770 INCHES MINIMUM AND 2.837 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | QQ-P-416 TY 1 FED SPEC 1ST TREATMENT RESPONSE OR QQ-P-416 TY 2 FED SPEC 2ND TREATMENT RESPONSE OVERALL |
| Thread Length | 0.316 INCHES MINIMUM IN |
| Shank Unthreaded Hole Diameter | 0.076 INCHES NOMINAL FIRST HOLE IN |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Grip Length | 2.470 INCHES MINIMUM AND 2.490 INCHES MAXIMUM IN |
| Grip Diameter | 0.2482 INCHES MINIMUM AND 0.2487 INCHES MAXIMUM IN |
| Surface Treatment | CADMIUM OR CADMIUM AND CHROMATE OVERALL |
| Minimum Tensile Strength | 180000 POUNDS PER SQUARE INCH LBS |
| Internal Drive Style | OFFSET CRUCIFORM (TORQUE SET) |
| Countersink Angle | 100.0 DEGREES NOMINAL |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 28 |
| Material | STEEL COMP 4340 OR STEEL COMP 4140 OR STEEL COMP 8740 OR STEEL COMP 6150 OR STEEL COMP E4340 OVERALL |
| Thread Series Designator | UNF |
| Distance From Head Largest Bearing Surface to Shank Hole Center | 0.116 INCHES NOMINAL FIRST HOLE IN |
| Head Diameter | 0.507 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 | F |
| Part Number | Manufacturer |
|---|---|
| 51B334-40H | Sps Technologies Llc Dba PB Fasteners Div PB Fasteners (USA) |
| 51B334-40H | Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc (CAN) |
| 51B334-40H | Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company (USA) |
| 51B334-40H | Hi-Shear Corporation (USA) |
| 51B334-40H | Sps Technologies, Llc Dba PB Fasteners (USA) |
| Reference | Meaning |
|---|---|
| 51B334-40H | 5/2 Secondary reference U.S. Government activity |
| 51B334-40H | 5/9 Secondary reference Berco Mfg Co |
| 51B334-40H | 3/9 Design control — primary reference Northrop Grumman Systems Corporation Dba Northrop Grumman Is Div Northrop Grumman Aeronautics Systems |
| 51B334-40H | C/1 Advisory reference — outside the item-of-supply concept Northrop Grumman Technical Services, Inc. Dba Defense Systems Sector |
NSN 5305-00-810-1266 is a Screw,close Tolerance, manufactured by Sps Technologies Llc Dba PB Fasteners Div PB Fasteners, classified under FSC 5305, Screws. Status: active.
NSN 5305-00-810-1266 has 5 manufacturer part numbers on file: 51B334-40H (Sps Technologies Llc Dba PB Fasteners Div PB Fasteners), 51B334-40H (Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc), 51B334-40H (Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company), 51B334-40H (Hi-Shear Corporation), 51B334-40H (Sps Technologies, Llc Dba PB Fasteners).
Key specifications for 51B334-40H: Fastener Length: 2.770 INCHES MINIMUM AND 2.837 INCHES MAXIMUM IN; Surface Treatment Document and Classification: QQ-P-416 TY 1 FED SPEC 1ST TREATMENT RESPONSE OR QQ-P-416 TY 2 FED SPEC 2ND TREATMENT RESPONSE OVERALL; Thread Length: 0.316 INCHES MINIMUM IN; Shank Unthreaded Hole Diameter: 0.076 INCHES NOMINAL FIRST HOLE IN. 19 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.