The Gear,helical, cataloged under National Stock Number 3020-00-147-1685, is classified within Federal Supply Class 3020 (Gears, Pulleys, Sprockets, and Transmission Chain) of the Mechanical Power Transmission Equipment group. The manufacturer of record is Graham Co Inc. Government technical data includes 17 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. 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 | 3020-00-147-1685 |
| Primary Part Number | G1252 |
| Item Name | Gear,helical |
| FSC / FSG | 3020 / 30 — Gears, Pulleys, Sprockets, and Transmission Chain |
| Manufacturer | Graham Co Inc |
| Status | ACTIVE |
| Helix Angle | 7.1166 DEGREES |
| Teeth Quantity | 120 |
| Body Style | PLAIN, SOLID |
| Tooth Direction | RIGHT |
| Bore Style | D BOTH ENDS |
| Mounting Hole Type and Quantity | 2 THREADED AXIALLY THROUGH BODY FIRST END |
| Teeth Type | SINGLE HELIX |
| Style Designator | HUBLESS |
| Pitch Diameter | 2.5190 INCHES MINIMUM AND 2.5220 INCHES MAXIMUM IN |
| Tooth Form | STANDARD |
| Mounting Hole Nominal Thread Size | 0.125 INCHES AXIALLY THROUGH BODY FIRST END IN |
| Nominal Outside Diameter | 2.563 INCHES IN |
| Pressure Angle | 20.0000 DEGREES |
| Bolt Hole Circle Nominal Diameter | 0.606 INCHES AXIALLY THROUGH BODY FIRST END IN |
| Mounting Hole Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) AXIALLY THROUGH BODY FIRST END |
| Attachment Method | MOUNTING HOLE |
| Face Nominal Width | 0.140 INCHES 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 |
|---|---|
| G1252 PRIMARY | Graham Co Inc (USA) |
NSN 3020-00-147-1685 is a Gear,helical, manufactured by Graham Co Inc, classified under FSC 3020, Gears, Pulleys, Sprockets, and Transmission Chain. Status: active.
NSN 3020-00-147-1685 has 1 manufacturer part number on file: G1252 (Graham Co Inc).
1 possible match (shared part number, not a government interchangeability claim): 3020-00-537-5032. Verify interchangeability with system specifications before substitution.
Key specifications for G1252: Helix Angle: 7.1166 DEGREES; Teeth Quantity: 120; Body Style: PLAIN, SOLID; Tooth Direction: RIGHT. 17 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.