The Countersink, cataloged under National Stock Number 5133-01-321-9309, is classified within Federal Supply Class 5133 (Drill Bits, Counterbores, and Countersinks: Hand and Machine) of the Hand Tools group. The manufacturer of record is Adept Fasteners, Inc. Div Innovative Tooling Services. Government technical data includes 13 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5133-01-321-9309 |
| Primary Part Number | 166C011-309B5 |
| Item Name | Countersink |
| FSC / FSG | 5133 / 51 — Drill Bits, Counterbores, and Countersinks: Hand and Machine |
| Manufacturer | Adept Fasteners, Inc. Div Innovative Tooling Services |
| Status | ACTIVE |
| Body Diameter | 0.750 INCHES NOMINAL IN |
| Cutting End Style | SPIRAL FLUTE BLUNT END |
| Nominal Thread Diameter | 0.375 INCHES IN |
| Cutting Rotation Direction | RIGHT-HAND |
| Features Provided | INTEGRAL PILOT |
| Thread Direction | RIGHT-HAND |
| Pilot Diameter | 0.309 INCHES NOMINAL IN |
| Shank Style | EXTERNALLY THREADED |
| Flute Quantity | 3 |
| Included Angle | 100.0 DEGREES NOMINAL |
| Material | STEEL OVERALL |
| Thread Series Designator | UNF |
| Thread Quantity | 24 PER INCH |
| 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 |
|---|---|
| 166C011-309B5 PRIMARY | Adept Fasteners, Inc. Div Innovative Tooling Services (USA) |
| Reference | Meaning |
|---|---|
| 166C011-309B5 | 5/9 Secondary reference Alvord-Polk, Inc. Dba Alvord-Polk Tool Company Div Alvord-Polk Tool |
| 5133PL1496669 | 6/9 Informative reference only Jednolity Indeks Materialowy - Uniform Material Index |
NSN 5133-01-321-9309 is a Countersink, manufactured by Adept Fasteners, Inc. Div Innovative Tooling Services, classified under FSC 5133, Drill Bits, Counterbores, and Countersinks: Hand and Machine. Status: active.
NSN 5133-01-321-9309 has 1 manufacturer part number on file: 166C011-309B5 (Adept Fasteners, Inc. Div Innovative Tooling Services).
Key specifications for 166C011-309B5: Body Diameter: 0.750 INCHES NOMINAL IN; Cutting End Style: SPIRAL FLUTE BLUNT END; Overall Length: 1.060 INCHES NOMINAL IN; Nominal Thread Diameter: 0.375 INCHES IN. 13 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.