The Pulley,groove, cataloged under National Stock Number 3020-00-008-7941, 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 Smith-Berger Marine, Inc. Government technical data includes 23 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 | 3020-00-008-7941 |
| Primary Part Number | 28121B |
| Item Name | Pulley,groove |
| FSC / FSG | 3020 / 30 — Gears, Pulleys, Sprockets, and Transmission Chain |
| Manufacturer | Smith-Berger Marine, Inc |
| Status | ACTIVE |
| Integral Cooling Vane | NOT INCLUDED |
| Hub Outside Diameter | 3.750 INCHES NOMINAL BOTH ENDS IN |
| Bore Feature | INCLUDED |
| Split Hub Feature | NOT INCLUDED |
| Bore Length | 2.500 INCHES NOMINAL IN |
| Design Form | WEBBED |
| Groove Radius | 0.344 INCHES NOMINAL IN |
| Outside Diameter | 9.0000 INCHES NOMINAL IN |
| Style Designator | WEBBED OR SPOKED |
| Material Document and Classification | SAE 1040 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Groove Depth | 0.581 INCHES NOMINAL IN |
| Bore Type | STRAIGHT |
| Bearings | NOT INCLUDED |
| Counterbore Depth | 1.109 INCHES NOMINAL IN |
| Groove Quantity | 1 |
| Counterbore Location | BOTH ENDS |
| Counterbore Diameter | 3.265 INCHES NOMINAL IN |
| Unable to Decode | UNABLE TO DECODE |
| Counterbore Feature | INCLUDED |
| Bore Diameter | 2.938 INCHES NOMINAL IN |
| Material | STEEL COMP 1040 OVERALL |
| Face Width | 2.5000 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 |
|---|---|
| 28121B PRIMARY | Smith-Berger Marine, Inc (USA) |
NSN 3020-00-008-7941 is a Pulley,groove, manufactured by Smith-Berger Marine, Inc, classified under FSC 3020, Gears, Pulleys, Sprockets, and Transmission Chain. Status: active.
NSN 3020-00-008-7941 has 1 manufacturer part number on file: 28121B (Smith-Berger Marine, Inc).
Key specifications for 28121B: Integral Cooling Vane: NOT INCLUDED; Hub Outside Diameter: 3.750 INCHES NOMINAL BOTH ENDS IN; Bore Feature: INCLUDED; Split Hub Feature: NOT INCLUDED. 23 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.