The Screw,close Tolerance, cataloged under National Stock Number 5305-01-066-9358, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Northrop Grumman Systems Corporation. Government technical data includes 22 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through both NSN and commercial part number lookups. 6 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5305-01-066-9358 |
| Primary Part Number | 51B333-25H |
| Item Name | Screw,close Tolerance |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Northrop Grumman Systems Corporation |
| Status | ACTIVE |
| Surface Finish | 32.0 MICROINCHES GRIP |
| Fastener Length | 1.822 INCHES MINIMUM AND 1.869 INCHES MAXIMUM IN |
| Surface Treatment Document and Classification | QQ-P-416 TY2 CL2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Thread Length | 0.250 INCHES MINIMUM AND 0.317 INCHES MAXIMUM IN |
| Hardness Rating | 39.0 ROCKWELL C MINIMUM AND 43.0 ROCKWELL C MAXIMUM OVERALL |
| Shank Unthreaded Hole Diameter | 0.060 INCHES MINIMUM AND 0.080 INCHES MAXIMUM FIRST HOLE IN |
| Material Document and Classification | MIL-S-5000 MIL SPEC 1ST MATERIAL RESPONSE OR MIL-S-5626 MIL SPEC 2ND MATERIAL RESPONSE OR MIL-S-6049 MIL SPEC 3RD MATERIAL RESPONSE OVERALL |
| Nominal Thread Diameter | 0.190 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Grip Length | 1.552 INCHES MINIMUM AND 1.572 INCHES MAXIMUM IN |
| Grip Diameter | 0.1885 INCHES MINIMUM AND 0.1895 INCHES MAXIMUM IN |
| Surface Treatment | CADMIUM AND CHROMATE OVERALL |
| Minimum Tensile Strength | 180000 POUNDS PER SQUARE INCH LBS |
| Internal Drive Style | OFFSET CRUCIFORM (TORQUE SET) |
| Countersink Angle | 99.5 DEGREES MINIMUM AND 100.5 DEGREES MAXIMUM |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 32 |
| Material | STEEL COMP E4340 OR STEEL COMP 4140 OR STEEL COMP 8740 OVERALL |
| Thread Series Designator | UNF |
| Distance From Head Largest Bearing Surface to Shank Hole Center | 1.695 INCHES MINIMUM AND 1.762 INCHES MAXIMUM FIRST HOLE IN |
| Head Diameter | 0.329 INCHES MINIMUM AND 0.385 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 |
|---|---|
| 51B333-25H PRIMARY | Northrop Grumman Systems Corporation (USA) |
| 51B333-25H | Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company (USA) |
| 51B333-25H | Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc (CAN) |
| 51B333-25H | Huck International, Inc (USA) |
| 51B333-25H | Hi-Shear Corporation (USA) |
| 51B333-25H | Howmet Global Fastening Systems Inc (USA) |
| Reference | Meaning |
|---|---|
| 51B333-25H | 5/2 Secondary reference U.S. Government activity |
| 51B333-25H | 5/2 Secondary reference U.S. Government activity |
| 51B333-25H | 3/9 Design control — primary reference Northrop Grumman Systems Corporation Dba Northrop Grumman Is Div Northrop Grumman Aeronautics Systems |
| 51B333-25H | 5/9 Secondary reference U.S. Government activity |
| 51B333-25H | 5/9 Secondary reference Northrop Grumman Technical Services, Inc. Dba Defense Systems Sector |
| 51B333-25H | 5/9 Secondary reference Sps Technologies Inc |
NSN 5305-01-066-9358 is a Screw,close Tolerance, manufactured by Northrop Grumman Systems Corporation, classified under FSC 5305, Screws. Status: active.
NSN 5305-01-066-9358 has 6 manufacturer part numbers on file: 51B333-25H (Northrop Grumman Systems Corporation), 51B333-25H (Sps Technologies, Llc Dba Air Industries Company Div Air Industries Company), 51B333-25H (Lisi Aerospace Canada Corp Div Hi Shear Holdings Inc), 51B333-25H (Huck International, Inc), 51B333-25H (Hi-Shear Corporation) and 1 more.
Key specifications for 51B333-25H: Surface Finish: 32.0 MICROINCHES GRIP; Fastener Length: 1.822 INCHES MINIMUM AND 1.869 INCHES MAXIMUM IN; Surface Treatment Document and Classification: QQ-P-416 TY2 CL2 FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Thread Length: 0.250 INCHES MINIMUM AND 0.317 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.