The Screw,cap,socket Head, cataloged under National Stock Number 5305-00-550-0129, is classified within Federal Supply Class 5305 (Screws) of the Hardware and Abrasives group. The manufacturer of record is Nylok Llc. Government technical data includes 16 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number 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through both NSN and commercial part number lookups. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 5305-00-550-0129 |
| Primary Part Number | NK509-8R6 |
| Item Name | Screw,cap,socket Head |
| FSC / FSG | 5305 / 53 — Screws |
| Manufacturer | Nylok Llc |
| Status | ACTIVE |
| Fastener Length | 0.406 INCHES NOMINAL IN |
| Thread Length | 0.312 INCHES MINIMUM IN |
| Hardness Rating | 26.0 ROCKWELL C MINIMUM AND 32.0 ROCKWELL C MAXIMUM OVERALL |
| Nominal Thread Diameter | 0.164 INCHES IN |
| Head Style | FLAT COUNTERSUNK |
| Thread Direction | RIGHT-HAND |
| Locking Feature | PATCH OR STRIP THREADS |
| Surface Treatment | CADMIUM OVERALL |
| Minimum Tensile Strength | 125000 POUNDS PER SQUARE INCH LBS |
| Internal Drive Style | CROSS RECESS TYPE 1 |
| Countersink Angle | 100.0 DEGREES NOMINAL |
| Thread Class | 3A A |
| Thread Quantity Per Inch | 32 |
| Material | STEEL OVERALL |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) |
| Head Diameter | 0.319 INCHES MINIMUM AND 0.332 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 |
|---|---|
| NK509-8R6 PRIMARY | Nylok Llc (USA) |
| Reference | Meaning |
|---|---|
| MILS7839 | 5/9 Secondary reference U.S. Government activity |
| MILS7839 | 5/9 Secondary reference U.S. Government activity |
| NK509-8R6 | C/1 Advisory reference — outside the item-of-supply concept Schaefer Inc |
| GS551B08S6 | 5/9 Secondary reference Northrop Grumman Systems Corporation |
NSN 5305-00-550-0129 is a Screw,cap,socket Head, manufactured by Nylok Llc, classified under FSC 5305, Screws. Status: active.
NSN 5305-00-550-0129 has 1 manufacturer part number on file: NK509-8R6 (Nylok Llc).
Key specifications for NK509-8R6: Fastener Length: 0.406 INCHES NOMINAL IN; Thread Length: 0.312 INCHES MINIMUM IN; Hardness Rating: 26.0 ROCKWELL C MINIMUM AND 32.0 ROCKWELL C MAXIMUM OVERALL; Nominal Thread Diameter: 0.164 INCHES IN. 16 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.