The Sprocket Wheel, cataloged under National Stock Number 3020-01-177-4021, 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 Martin Sprocket and Gear Inc. Government technical data includes 22 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 3020-01-177-4021 |
| Primary Part Number | 40BS15 3/4 IN BORE |
| Item Name | Sprocket Wheel |
| FSC / FSG | 3020 / 30 — Gears, Pulleys, Sprockets, and Transmission Chain |
| Manufacturer | Martin Sprocket and Gear Inc |
| Status | ACTIVE |
| Hub Outside Diameter | 1.812 INCHES NOMINAL AA END IN |
| Bore Length | 0.875 INCHES NOMINAL IN |
| Design Form | PLAIN |
| Tooth Pitch | 0.500 INCHES NOMINAL IN |
| Asa Standard Chain Number | 40 |
| Outside Diameter | 2.650 INCHES NOMINAL IN |
| Keying Facility Type | KEYWAY |
| Quantity | 1 |
| Style Designator | PLAIN |
| Pitch Diameter | 2.405 INCHES NOMINAL IN |
| Bore Type | STRAIGHT |
| Teeth Row Quantity | 1 |
| Teeth Quantity Per Row | 15 |
| Protruding Hub Characteristic | PLAIN |
| Hardness Rating Test Method | NOT RATED |
| Distance From Center of Bore to Bottom of Keyway | 0.562 INCHES NOMINAL IN |
| Distance From Hub End to Flange End | 0.591 INCHES NOMINAL AA END IN |
| Keyway Width | 0.375 INCHES NOMINAL IN |
| Bore Diameter | 0.750 INCHES NOMINAL IN |
| Material | STEEL |
| Furnished Items | KEYING FACILITY |
| Face Width | 0.284 INCHES NOMINAL 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 |
|---|---|
| 40BS15 3/4 IN BORE PRIMARY | Martin Sprocket and Gear Inc (USA) |
| Reference | Meaning |
|---|---|
| 40BS15 | 5/9 Secondary reference Martin Sprocket and Gear Inc |
NSN 3020-01-177-4021 is a Sprocket Wheel, manufactured by Martin Sprocket and Gear Inc, classified under FSC 3020, Gears, Pulleys, Sprockets, and Transmission Chain. Status: active.
NSN 3020-01-177-4021 has 1 manufacturer part number on file: 40BS15 3/4 IN BORE (Martin Sprocket and Gear Inc).
Key specifications for 40BS15 3/4 IN BORE: Hub Outside Diameter: 1.812 INCHES NOMINAL AA END IN; Bore Length: 0.875 INCHES NOMINAL IN; Design Form: PLAIN; Tooth Pitch: 0.500 INCHES NOMINAL IN. 22 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.