The Cutter,countersink, cataloged under National Stock Number 5133-01-397-3228, 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 Idsc Holdings Llc Div Snap-on Industrial, a Div. of Idsc Holdings , Llc. Government technical data includes 11 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5133-01-397-3228 |
| Primary Part Number | ATI445E-4-1/4 |
| Item Name | Cutter,countersink |
| FSC / FSG | 5133 / 51 — Drill Bits, Counterbores, and Countersinks: Hand and Machine |
| Manufacturer | Idsc Holdings Llc Div Snap-on Industrial, a Div. of Idsc Holdings , Llc |
| Status | ACTIVE |
| Body Diameter | 0.500 INCHES NOMINAL IN |
| Cutting End Style | STRAIGHT FLUTE BLUNT END |
| Nominal Thread Diameter | 0.250 INCHES IN |
| Features Provided | INTEGRAL PILOT |
| Pilot Diameter | 0.250 INCHES NOMINAL IN |
| Nondefinitive Spec/std Data | 2 TYPE AND A STYLE |
| Shank Style | EXTERNALLY THREADED |
| Flute Quantity | 2 |
| Included Angle | 100.0 DEGREES NOMINAL |
| Thread Series Designator | UNF |
| Thread Quantity | 28 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 |
|---|---|
| ATI445E-4-1/4 | Idsc Holdings Llc Div Snap-on Industrial, a Div. of Idsc Holdings , Llc (USA) |
| Reference | Meaning |
|---|---|
| AT445E-4-1/4 | 5/9 Secondary reference Snap-on Incorporated Dba Snap-on Tools Div Snap-on Industrial, Special Products Division |
| A-A-58076 TY2STA | 5/1 Secondary reference U.S. Government activity |
| A-A-58076 | 4/1 Identification reference Federal Commercial Item Description Promulgated by General Services Administration Washington DC |
NSN 5133-01-397-3228 is a Cutter,countersink, manufactured by Idsc Holdings Llc Div Snap-on Industrial, a Div. of Idsc Holdings , Llc, classified under FSC 5133, Drill Bits, Counterbores, and Countersinks: Hand and Machine. Status: active.
NSN 5133-01-397-3228 has 1 manufacturer part number on file: ATI445E-4-1/4 (Idsc Holdings Llc Div Snap-on Industrial, a Div. of Idsc Holdings , Llc).
1 possible match (shared part number, not a government interchangeability claim): 5133-01-428-5685. Verify interchangeability with system specifications before substitution.
Key specifications for ATI445E-4-1/4: Body Diameter: 0.500 INCHES NOMINAL IN; Cutting End Style: STRAIGHT FLUTE BLUNT END; Nominal Thread Diameter: 0.250 INCHES IN; Features Provided: INTEGRAL PILOT. 11 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.