The Block,tackle, cataloged under National Stock Number 3940-00-461-1539, is classified within Federal Supply Class 3940 (Blocks, Tackle, Rigging, and Slings) of the Materials Handling Equipment group. Government technical data includes 24 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 3940-00-461-1539 |
| Item Name | Block,tackle |
| FSC / FSG | 3940 / 39 — Blocks, Tackle, Rigging, and Slings |
| Status | ACTIVE |
| Attachment Style | OBLONG SWIVEL EYE AND SHACKLE |
| Sheave Bearing Lubrication Method | SELF-LUBRICATED |
| Maximum Tackle Diameter Accommodated | 1.000 INCHES IN |
| Load Rating | 20000.0 POUNDS MAXIMUM LBS |
| Tackle Locking Device | NOT INCLUDED |
| Sheave Outside Diameter | 18.000 INCHES NOMINAL IN |
| Tackle Accommodated Type | WIRE ROPE |
| Block Type | SNATCH |
| Center Pin Diameter | 1.500 INCHES NOMINAL IN |
| Style Designator | OVAL PATTERN |
| Material Document and Classification | ASTM A47 ASSN STD 1ST MATERIAL RESPONSE AND QQ-S-633-CANCELED FED SPEC 2ND MATERIAL RESPONSE AND QQ-S-681 FED SPEC 2ND MATERIAL RESPONSE SHELL |
| Material Document and Classification | FED STD 66 FED STD SINGLE MATERIAL RESPONSE OR AISI 1040 ASSN STD SINGLE MATERIAL RESPONSE OR SAE 1040 ASSN STD SINGLE MATERIAL RESPONSE CENTER PIN |
| Material Document and Classification | QQ-S-681 FED SPEC SINGLE MATERIAL RESPONSE SHEAVE |
| Locking Style | SAFETY LOCKING |
| Nondefinitive Spec/std Data | 3 TYPE |
| Bearing Type | PLAIN |
| Surface Treatment | ZINC OVERALL |
| Sheave Quantity | 1 |
| Material | STEEL SHEAVE |
| Material | COPPER ALLOY BEARING |
| Material | IRON CAST UNS F22200 AND STEEL SHELL COMPOSITION ONE |
| Material | IRON CAST UNS F22400 AND STEEL SHELL COMPOSITION TWO |
| Material | STEEL COMP 1040 CENTER PIN |
| 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 |
|---|---|
| MILB24141 | 4/1 Identification reference U.S. Government activity |
| 4084HU | 5/9 Secondary reference Brewer-Titchner Corp Sub Joslyn Mfg and Supply Co |
NSN 3940-00-461-1539 is a Block,tackle, classified under FSC 3940, Blocks, Tackle, Rigging, and Slings. Status: active.
1 possible match (shared part number, not a government interchangeability claim): 3940-01-373-2733. Verify interchangeability with system specifications before substitution.
Key specifications for 3940-00-461-1539: Attachment Style: OBLONG SWIVEL EYE AND SHACKLE; Sheave Bearing Lubrication Method: SELF-LUBRICATED; Maximum Tackle Diameter Accommodated: 1.000 INCHES IN; Load Rating: 20000.0 POUNDS MAXIMUM LBS. 24 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.