The Chain,roller, cataloged under National Stock Number 3020-01-451-3780, 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 Naval Sea Systems Command. Government technical data includes 2 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through both NSN and commercial part number lookups. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 3020-01-451-3780 |
| Primary Part Number | 56W42-2PC17 |
| Item Name | Chain,roller |
| FSC / FSG | 3020 / 30 — Gears, Pulleys, Sprockets, and Transmission Chain |
| Manufacturer | Naval Sea Systems Command |
| Status | ACTIVE |
| Nominal Pitch Distance | 1.250 INCHES IN |
| Pin Fastening Method | COTTER PIN |
| 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 |
|---|---|
| 56W42-2PC17 | Naval Sea Systems Command (USA) |
| Reference | Meaning |
|---|---|
| 56W42-2 | D/9 Drawing number reference only Naval Sea Systems Command |
| SIZE 120 COTTERED | 3/9 Design control — primary reference Rexnord Industries Inc. Div Roller Chain Operation |
| SIZE 120 C0TTER | C/1 Advisory reference — outside the item-of-supply concept Rexnord Industries Inc. Div Roller Chain Operation |
| 4777-69-2PC17 | 5/9 Secondary reference Advanced Marine Enterprises Inc North East Div |
NSN 3020-01-451-3780 is a Chain,roller, manufactured by Naval Sea Systems Command, classified under FSC 3020, Gears, Pulleys, Sprockets, and Transmission Chain. Status: active.
NSN 3020-01-451-3780 has 1 manufacturer part number on file: 56W42-2PC17 (Naval Sea Systems Command).
Key specifications for 56W42-2PC17: Nominal Pitch Distance: 1.250 INCHES IN; Pin Fastening Method: COTTER PIN; End Item Identification: STRATEGIC SEALIFT CONVERSION SHIPS CLASS. 2 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.