The Heat Sink,electrical-Electronic, cataloged under National Stock Number 5999-01-677-9303, is classified within Federal Supply Class 5999 (Miscellaneous Electrical and Electronic Components) of the Electrical and Electronic Equipment Components group. Government technical data includes 8 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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. Unit of issue: EA.
| Parameter | Value |
|---|---|
| NSN | 5999-01-677-9303 |
| Item Name | Heat Sink,electrical-Electronic |
| FSC / FSG | 5999 / 59 — Miscellaneous Electrical and Electronic Components |
| Status | ACTIVE |
| Mounting Facility Type and Quantity | 4 UNTHREADED HOLE(S) ALL MOUNTING FACILITIES |
| Body Style | HORIZONTALLY MOUNTED |
| Unthreaded Mounting Hole Diameter | 0.19 INCHES NOMINAL FIRST MOUNTING FACILITY IN |
| Unthreaded Mounting Hole Diameter | 0.22 INCHES NOMINAL SECOND MOUNTING FACILITY IN |
| Specification/standard Data | 80205-NAS4121 NATIONAL STD/SPEC |
| Surface Treatment | ANODIZE |
| Material | ALUMINUM |
| Accommodated Device Mounting Hole Quantity | 4 |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | Possible hazard — SDS may be required (DLA HMIC P) |
| Shelf Life Code | 0 |
| Criticality Code | X |
| Unit of Issue | EA |
| Acquisition advice code | JZ |
| Reference | Meaning |
|---|---|
| NAS4121-084B | 3/2 Design control — primary reference U.S. Government activity |
| NAS4121 | 3/1 Design control — primary reference U.S. Government activity |
NSN 5999-01-677-9303 is a Heat Sink,electrical-Electronic, classified under FSC 5999, Miscellaneous Electrical and Electronic Components. Status: active.
1 possible match (shared part number, not a government interchangeability claim): 5999-01-683-0016. Verify interchangeability with system specifications before substitution.
Key specifications for 5999-01-677-9303: Mounting Facility Type and Quantity: 4 UNTHREADED HOLE(S) ALL MOUNTING FACILITIES; Overall Height: 0.750 INCHES NOMINAL IN; Body Style: HORIZONTALLY MOUNTED; Unthreaded Mounting Hole Diameter: 0.19 INCHES NOMINAL FIRST MOUNTING FACILITY IN. 8 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.