The Plug,fusible, cataloged under National Stock Number 5340-01-121-8779, is classified within Federal Supply Class 5340 (Hardware, Commercial) of the Hardware and Abrasives group. The manufacturer of record is Kovatch Corp.. Government technical data includes 7 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active. Unit of issue: EA.
| Parameter | Value |
|---|---|
| NSN | 5340-01-121-8779 |
| Primary Part Number | K-500-F-4021 |
| Item Name | Plug,fusible |
| FSC / FSG | 5340 / 53 — Hardware, Commercial |
| Manufacturer | Kovatch Corp. |
| Status | ACTIVE |
| Material Document and Classification | COMP 316 NATIONAL SPEC SINGLE MATERIAL RESPONSE CASING |
| Features Provided | CORE |
| Size Designation | 2 INCH IN |
| Core Fusing Temp Rating | 250.0 DEG FAHRENHEIT |
| Material | STEEL CORROSION RESISTING CASING |
| Thread Size and Series/type Designator | 2-11 1/2 NPT |
| Usage Location | OUTSIDE |
| 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 |
|---|---|
| K-500-F-4021 | Kovatch Corp. (USA) |
| Reference | Meaning |
|---|---|
| T-3322-SS | 3/9 Design control — primary reference Betts Industries, Inc. |
NSN 5340-01-121-8779 is a Plug,fusible, manufactured by Kovatch Corp., classified under FSC 5340, Hardware, Commercial. Status: active.
NSN 5340-01-121-8779 has 1 manufacturer part number on file: K-500-F-4021 (Kovatch Corp.).
Key specifications for K-500-F-4021: Material Document and Classification: COMP 316 NATIONAL SPEC SINGLE MATERIAL RESPONSE CASING; Features Provided: CORE; Size Designation: 2 INCH IN; Core Fusing Temp Rating: 250.0 DEG FAHRENHEIT. 7 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.