The Gear,helical, cataloged under National Stock Number 3020-00-652-9951, 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 Army, United States Department of the Dba Rock Island Arsenal Jmtc. 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 3020-00-652-9951 |
| Primary Part Number | 8421843 |
| Item Name | Gear,helical |
| FSC / FSG | 3020 / 30 — Gears, Pulleys, Sprockets, and Transmission Chain |
| Manufacturer | Army, United States Department of the Dba Rock Island Arsenal Jmtc |
| Status | ACTIVE |
| Keyway Nominal Width | 0.145 INCHES BOTH ENDS IN |
| Bore Nominal Diameter | 0.447 INCHES BOTH ENDS IN |
| Helix Angle | 11.7301 DEGREES |
| Teeth Quantity | 40 |
| Body Style | PLAIN, SOLID |
| Tooth Direction | RIGHT |
| Bore Style | W/ KEYWAY BOTH ENDS |
| Teeth Type | SINGLE HELIX |
| Style Designator | HUBLESS |
| Material Document and Classification | QQ-C-390,ALLOY E8 FED SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Pitch Diameter | 1.2766 INCHES NOMINAL IN |
| Tooth Form | STANDARD |
| Nominal Outside Diameter | 1.329 INCHES IN |
| Nominal Distance From Bore Center to Keyway Bottom | 0.322 INCHES BOTH ENDS IN |
| Pressure Angle | 20.0000 DEGREES |
| Material | COPPER ALLOY 934 OVERALL |
| Face Nominal Width | 0.310 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 |
|---|---|
| 8421843 PRIMARY | Army, United States Department of the Dba Rock Island Arsenal Jmtc (USA) |
| Reference | Meaning |
|---|---|
| 5097507 | 5/9 Secondary reference General Motors Corp Delco Products Div |
| 5097507 | C/1 Advisory reference — outside the item-of-supply concept General Motors Llc Dba General Motors Llc |
| 5097507 | 5/9 Secondary reference General Motors Corp |
NSN 3020-00-652-9951 is a Gear,helical, manufactured by Army, United States Department of the Dba Rock Island Arsenal Jmtc, classified under FSC 3020, Gears, Pulleys, Sprockets, and Transmission Chain. Status: active.
NSN 3020-00-652-9951 has 1 manufacturer part number on file: 8421843 (Army, United States Department of the Dba Rock Island Arsenal Jmtc).
Key specifications for 8421843: Keyway Nominal Width: 0.145 INCHES BOTH ENDS IN; Bore Nominal Diameter: 0.447 INCHES BOTH ENDS IN; Helix Angle: 11.7301 DEGREES; Teeth Quantity: 40. 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.