The Block,tackle, cataloged under National Stock Number 3940-00-468-8521, is classified within Federal Supply Class 3940 (Blocks, Tackle, Rigging, and Slings) of the Materials Handling Equipment group. Government technical data includes 14 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government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 | 3940-00-468-8521 |
| Item Name | Block,tackle |
| FSC / FSG | 3940 / 39 — Blocks, Tackle, Rigging, and Slings |
| Status | ACTIVE |
| Attachment Style | STIFF, UPSET SWIVEL SHACKLE |
| Maximum Tackle Diameter Accommodated | 0.750 INCHES IN |
| Tackle Locking Device | NOT INCLUDED |
| Sheave Outside Diameter | 12.500 INCHES NOMINAL IN |
| Tackle Accommodated Type | WIRE ROPE |
| Block Type | REGULAR |
| Center Pin Diameter | 1.497 INCHES NOMINAL IN |
| Style Designator | ROUND PATTERN |
| Surface Treatment | ZINC OVERALL |
| Sheave Quantity | 1 |
| Material | STEEL SHELL |
| Material | STEEL BEARING |
| Material | COPPER ALLOY 861 OR COPPER ALLOY 862 OR COPPER ALLOY 863 SHEAVE |
| Antitoppling Device | 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 |
| Reference | Meaning |
|---|---|
| 216-381 | 3/2 Design control — primary reference U.S. Government activity |
| 544535 | 3/2 Design control — primary reference U.S. Government activity |
NSN 3940-00-468-8521 is a Block,tackle, classified under FSC 3940, Blocks, Tackle, Rigging, and Slings. Status: active.
2 possible matches (shared part number, not a government interchangeability claim): 3110-01-050-3781, 4810-01-142-3980. Verify interchangeability with system specifications before substitution.
Key specifications for 3940-00-468-8521: Attachment Style: STIFF, UPSET SWIVEL SHACKLE; Maximum Tackle Diameter Accommodated: 0.750 INCHES IN; Tackle Locking Device: NOT INCLUDED; Sheave Outside Diameter: 12.500 INCHES NOMINAL IN. 14 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.