The Block,tackle, cataloged under National Stock Number 3940-01-458-4438, is classified within Federal Supply Class 3940 (Blocks, Tackle, Rigging, and Slings) of the Materials Handling Equipment group. The manufacturer of record is Harken Inc. 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. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 3940-01-458-4438 |
| Primary Part Number | 021 |
| Item Name | Block,tackle |
| FSC / FSG | 3940 / 39 — Blocks, Tackle, Rigging, and Slings |
| Manufacturer | Harken Inc |
| Status | ACTIVE |
| Maximum Tackle Diameter Accommodated | 1.750 INCHES IN |
| Tackle Accommodated Type | WIRE ROPE |
| 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 |
|---|---|
| 021 PRIMARY | Harken Inc (USA) |
NSN 3940-01-458-4438 is a Block,tackle, manufactured by Harken Inc, classified under FSC 3940, Blocks, Tackle, Rigging, and Slings. Status: active.
NSN 3940-01-458-4438 has 1 manufacturer part number on file: 021 (Harken Inc).
2 possible matches (shared part number, not a government interchangeability claim): 4220-01-487-6439, 8145-01-524-7273. Verify interchangeability with system specifications before substitution.
Key specifications for 021: Maximum Tackle Diameter Accommodated: 1.750 INCHES IN; Tackle Accommodated Type: WIRE ROPE; End Item Identification: USED ON SAILBOAT. 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.