The Standoff,threaded,spacing, cataloged under National Stock Number 5340-01-640-7940, is classified within Federal Supply Class 5340 (Hardware, Commercial) of the Hardware and Abrasives group. The manufacturer of record is The Boeing Company Div Defense. Government technical data includes 18 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. Current acquisition status: Active. Unit of issue: EA.
| Parameter | Value |
|---|---|
| NSN | 5340-01-640-7940 |
| Primary Part Number | ST4M138-08-56 |
| Item Name | Standoff,threaded,spacing |
| FSC / FSG | 5340 / 53 — Hardware, Commercial |
| Manufacturer | The Boeing Company Div Defense |
| Status | ACTIVE |
| Left Countersink Angle | 115.0 DEGREES MINIMUM AND 125.0 DEGREES MAXIMUM |
| Width Across Flats | 0.312 INCHES NOMINAL IN |
| Length | 5.50 INCHES MINIMUM AND 5.70 INCHES MAXIMUM IN |
| Thread Length | 0.223 INCHES NOMINAL LEFT INTERNAL (INCLUDES THRU THREAD) IN |
| Thread Length | 0.223 INCHES NOMINAL RIGHT INTERNAL IN |
| Style Designator | LEFT INTERNAL AND RIGHT INTERNAL THREADS |
| Thread Direction | RIGHT-HAND LEFT INTERNAL (INCLUDES THRU THREAD) |
| Thread Direction | RIGHT-HAND RIGHT INTERNAL |
| Nominal Thread Size | 0.164 INCHES RIGHT INTERNAL IN |
| Nominal Thread Size | 0.164 INCHES LEFT INTERNAL (INCLUDES THRU THREAD) IN |
| Cross-Sectional Shape | HEXAGON |
| Right Countersink Angle | 115.0 DEGREES MINIMUM AND 125.0 DEGREES MAXIMUM |
| Thread Class | 2B LEFT INTERNAL (INCLUDES THRU THREAD) |
| Thread Class | 2B RIGHT INTERNAL |
| Thread Quantity Per Inch | 32 RIGHT INTERNAL |
| Thread Quantity Per Inch | 32 LEFT INTERNAL (INCLUDES THRU THREAD) |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) LEFT INTERNAL (INCLUDES THRU THREAD) |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) RIGHT INTERNAL |
| 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 |
|---|---|
| ST4M138-08-56 PRIMARY | The Boeing Company Div Defense (USA) |
NSN 5340-01-640-7940 is a Standoff,threaded,spacing, manufactured by The Boeing Company Div Defense, classified under FSC 5340, Hardware, Commercial. Status: active.
NSN 5340-01-640-7940 has 1 manufacturer part number on file: ST4M138-08-56 (The Boeing Company Div Defense).
Key specifications for ST4M138-08-56: Left Countersink Angle: 115.0 DEGREES MINIMUM AND 125.0 DEGREES MAXIMUM; Width Across Flats: 0.312 INCHES NOMINAL IN; Length: 5.50 INCHES MINIMUM AND 5.70 INCHES MAXIMUM IN; Thread Length: 0.223 INCHES NOMINAL LEFT INTERNAL (INCLUDES THRU THREAD) IN. 18 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.