The Clamp,block,section, cataloged under National Stock Number 5340-01-042-5285, is classified within Federal Supply Class 5340 (Hardware, Commercial) of the Hardware and Abrasives group. The manufacturer of record is Northrop Grumman Systems Corporation. Government technical data includes 20 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active. Unit of issue: EA.
| Parameter | Value |
|---|---|
| NSN | 5340-01-042-5285 |
| Primary Part Number | A51L21079-33 |
| Item Name | Clamp,block,section |
| FSC / FSG | 5340 / 53 — Hardware, Commercial |
| Manufacturer | Northrop Grumman Systems Corporation |
| Status | ACTIVE |
| Mounting Hole Quantity | 22 |
| Clamping Hole Quantity | 55 |
| Center to Center Distance Between First and Fourth Clamping Holes | 1.578 INCHES NOMINAL IN |
| Distance From End to First Clamping Hole Center | 0.250 INCHES NOMINAL IN |
| Block Height | 0.375 INCHES NOMINAL0.375 INCHES NOMINAL IN |
| Style Designator | RECTANGULAR |
| Mounting Hole Diameter | 0.190 INCHES MINIMUM AND 0.190 INCHES MINIMUM AND 0.196 INCHES MAXIMUM0.196 INCHES MAXIMUM IN |
| Clamping Hole Diameter | 0.188 INCHES MINIMUM AND 0.192 INCHES MAXIMUM SECOND HOLE IN |
| Clamping Hole Diameter | 0.250 INCHES MINIMUM AND 0.254 INCHES MAXIMUM FIFTH HOLE IN |
| Clamping Hole Diameter | 0.250 INCHES MINIMUM AND 0.254 INCHES MAXIMUM FIRST HOLE IN |
| Clamping Hole Diameter | 0.250 INCHES MINIMUM AND 0.254 INCHES MAXIMUM FOURTH HOLE IN |
| Clamping Hole Diameter | 0.250 INCHES MINIMUM AND 0.254 INCHES MAXIMUM THIRD HOLE IN |
| Center to Center Distance Between First and Third Clamping Holes | 1.070 INCHES NOMINAL IN |
| Distance From Center of Mounting Hole to Edge Along the Width | 0.188 INCHES NOMINAL0.188 INCHES NOMINAL IN |
| Distance From End to First Mounting Hole Center | 0.562 INCHES NOMINAL IN |
| Mounting Facility | UNTHREADED HOLE(S)UNTHREADED HOLE(S) |
| Center to Center Distance Between First and Fifth Clamping Holes | 2.086 INCHES NOMINAL IN |
| Center to Center Distance Between First and Second Mounting Holes | 2.087 INCHES NOMINAL2.087 INCHES NOMINAL IN |
| Material | PLASTIC |
| Center to Center Distance Between First and Second Clamping Holes | 0.593 INCHES NOMINAL IN |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | Possible hazard — SDS may be required (DLA HMIC P) |
| Criticality Code | X |
| Unit of Issue | EA |
| Part Number | Manufacturer |
|---|---|
| A51L21079-33 PRIMARY | Northrop Grumman Systems Corporation (USA) |
| Reference | Meaning |
|---|---|
| A51L21079-33 | 5/9 Secondary reference Northrop Grumman Systems Corporation |
| A51L21079-33 | 3/9 Design control — primary reference Northrop Grumman Systems Corporation Dba Northrop Grumman Systems Corp Div Northrop Grumman Aeronautics Systems |
NSN 5340-01-042-5285 is a Clamp,block,section, manufactured by Northrop Grumman Systems Corporation, classified under FSC 5340, Hardware, Commercial. Status: active.
NSN 5340-01-042-5285 has 1 manufacturer part number on file: A51L21079-33 (Northrop Grumman Systems Corporation).
Key specifications for A51L21079-33: Mounting Hole Quantity: 22; Clamping Hole Quantity: 55; Center to Center Distance Between First and Fourth Clamping Holes: 1.578 INCHES NOMINAL IN; Distance From End to First Clamping Hole Center: 0.250 INCHES NOMINAL IN. 20 specifications are documented in the U.S. Government catalog.
Possible hazard — SDS may be required (DLA HMIC P). 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.