The Gear,spur, cataloged under National Stock Number 3020-01-121-2961, 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 Aimtron Systems, Llc. Government technical data includes 20 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 3020-01-121-2961 |
| Primary Part Number | 503449 |
| Item Name | Gear,spur |
| FSC / FSG | 3020 / 30 — Gears, Pulleys, Sprockets, and Transmission Chain |
| Manufacturer | Aimtron Systems, Llc |
| Status | ACTIVE |
| Keyway Nominal Width | 0.250 INCHES BOTH ENDS IN |
| Bore Nominal Diameter | 2.937 INCHES BOTH ENDS IN |
| Hub Nominal Diameter | 4.000 INCHES SECOND END IN |
| Hub Nominal Diameter | 4.000 INCHES FIRST END IN |
| Teeth Quantity | 270 |
| Surface Treatment Document and Classification | MIL-F-14072,FINISH E300 MIL SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Body Style | PLAIN, SOLID |
| Bore Style | W/ KEYWAY BOTH ENDS |
| Nominal Distance Between Body Face and Protruding Hub End | 0.656 INCHES FIRST END IN |
| Style Designator | PROTRUDING HUBS |
| Material Document and Classification | QQ-S-763,CLASS 303,COND A FED SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Pitch Diameter | 5.6250 INCHES NOMINAL IN |
| Tooth Form | STANDARD |
| Hub Style Designator | PLAIN BOTH ENDS |
| Nominal Outside Diameter | 5.666 INCHES IN |
| Nominal Distance From Bore Center to Keyway Bottom | 1.593 INCHES BOTH ENDS IN |
| Surface Treatment | PASSIVATE OVERALL |
| Pressure Angle | 20.0000 DEGREES |
| Material | STEEL COMP 303 OVERALL |
| Face Nominal Width | 0.125 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 |
NSN 3020-01-121-2961 is a Gear,spur, manufactured by Aimtron Systems, Llc, classified under FSC 3020, Gears, Pulleys, Sprockets, and Transmission Chain. Status: active.
NSN 3020-01-121-2961 has 2 manufacturer part numbers on file: 503449 (Aimtron Systems, Llc), 1212961 (American Precision Gear Company Dba American Precision Gear Co Div Same).
1 possible match (shared part number, not a government interchangeability claim): 5340-01-565-8850. Verify interchangeability with system specifications before substitution.
Key specifications for 503449: Keyway Nominal Width: 0.250 INCHES BOTH ENDS IN; Bore Nominal Diameter: 2.937 INCHES BOTH ENDS IN; Hub Nominal Diameter: 4.000 INCHES SECOND END IN; Hub Nominal Diameter: 4.000 INCHES FIRST END IN. 20 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.