The Pulley,groove, cataloged under National Stock Number 3020-01-437-6959, 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 Efson Inc. Government technical data includes 18 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. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 3020-01-437-6959 |
| Primary Part Number | RA4501 |
| Item Name | Pulley,groove |
| FSC / FSG | 3020 / 30 — Gears, Pulleys, Sprockets, and Transmission Chain |
| Manufacturer | Efson Inc |
| Status | ACTIVE |
| Integral Cooling Vane | NOT INCLUDED |
| Bore Feature | INCLUDED |
| Design Form | WEBBED |
| Web/spoke Relationship to Face Centerline | NOT OFFSET |
| Groove Shape | U |
| Outside Diameter | 4.500 INCHES NOMINAL IN |
| Style Designator | WEBBED OR SPOKED |
| Pitch Diameter | 4.115 INCHES NOMINAL IN |
| Groove Depth | 0.385 INCHES NOMINAL IN |
| Bore Type | STRAIGHT |
| Bearings | INCLUDED |
| Groove Quantity | 1 |
| Bearing Type | BALL |
| Bore Diameter | 0.669 INCHES NOMINAL IN |
| Material | PLASTIC OVERALL |
| Face Width | 0.800 INCHES NOMINAL IN |
| Groove Width | 0.440 INCHES NOMINAL IN |
| Lightening Hole | NOT INCLUDED |
| 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 |
|---|---|
| RA4501 PRIMARY | Efson Inc (USA) |
NSN 3020-01-437-6959 is a Pulley,groove, manufactured by Efson Inc, classified under FSC 3020, Gears, Pulleys, Sprockets, and Transmission Chain. Status: active.
NSN 3020-01-437-6959 has 1 manufacturer part number on file: RA4501 (Efson Inc).
Key specifications for RA4501: Integral Cooling Vane: NOT INCLUDED; Bore Feature: INCLUDED; Design Form: WEBBED; Web/spoke Relationship to Face Centerline: NOT OFFSET. 18 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.