The Phase Changing Unit, cataloged under National Stock Number 4920-00-170-9245, is classified within Federal Supply Class 4920 (Aircraft Maintenance and Repair Shop Specialized Equipment) of the Maintenance and Repair Shop Equipment group. The manufacturer of record is H R Smith (technical Developments) Ltd. 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Item Name | Phase Changing Unit |
| FSC / FSG | 4920 — Aircraft Maintenance and Repair Shop Specialized Equipment (FSG 49) |
| Manufacturers | H R Smith (technical Developments) Ltd (CAGE K6543) |
| Parameter | Value |
|---|---|
| NSN | 4920-00-170-9245 |
| Primary Part Number | 12601-1 |
| Item Name | Phase Changing Unit |
| FSC / FSG | 4920 / 49 — Aircraft Maintenance and Repair Shop Specialized Equipment |
| Manufacturer | H R Smith (technical Developments) Ltd |
| Status | ACTIVE |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Part Number | Manufacturer |
|---|---|
| 12601-1 PRIMARY | H R Smith (technical Developments) Ltd (GBR) |
| Reference | Meaning |
|---|---|
| 12-601-1 | 5/9 Secondary reference H R Smith (technical Developments) Ltd |
NSN 4920-00-170-9245 is a Phase Changing Unit, manufactured by H R Smith (technical Developments) Ltd, classified under FSC 4920, Aircraft Maintenance and Repair Shop Specialized Equipment. Status: active.
NSN 4920-00-170-9245 has 1 manufacturer part number on file: 12601-1 (H R Smith (technical Developments) Ltd).
2 possible matches (shared part number, not a government interchangeability claim): 5935-00-420-0327, 5305-01-409-0271. Verify interchangeability with system specifications before substitution.
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.