The Counterbore,machine, cataloged under National Stock Number 5133-00-596-6221, is classified within Federal Supply Class 5133 (Drill Bits, Counterbores, and Countersinks: Hand and Machine) of the Hand Tools group. Government technical data includes 8 specifications, cited from the U.S. Government catalog. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5133-00-596-6221 |
| Item Name | Counterbore,machine |
| FSC / FSG | 5133 / 51 — Drill Bits, Counterbores, and Countersinks: Hand and Machine |
| Status | ACTIVE |
| Shank Diameter | 0.2500 INCHES NOMINAL IN |
| Cutting End Style | INTERCHANGEABLE PILOT |
| Nominal Cutting Diameter | 0.2500 INCHES IN |
| Features Provided | REPLACEABLE PILOT |
| Shank Style | STRAIGHT ROUND |
| Pilot Hole Nominal Diameter | 0.0938 INCHES IN |
| Flute Quantity | 4 |
| Material | STEEL OVERALL |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| AT488-1 | 5/9 Secondary reference Snap-on Incorporated Dba Snap-on Tools Div Snap-on Industrial, Special Products Division |
| AT488C-1 | 3/9 Design control — primary reference Snap-on Incorporated Dba Snap-on Tools Div Snap-on Industrial, Special Products Division |
| AT488C-1 | C/1 Advisory reference — outside the item-of-supply concept Idsc Holdings Llc Div Snap-on Industrial, a Div. of Idsc Holdings , Llc |
NSN 5133-00-596-6221 is a Counterbore,machine, classified under FSC 5133, Drill Bits, Counterbores, and Countersinks: Hand and Machine. Status: active.
Key specifications for 5133-00-596-6221: Shank Diameter: 0.2500 INCHES NOMINAL IN; Cutting End Style: INTERCHANGEABLE PILOT; Overall Length: 2.000 INCHES NOMINAL IN; Nominal Cutting Diameter: 0.2500 INCHES IN. 8 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.