The Heating Element,electrical,nonim, cataloged under National Stock Number 4520-00-281-3666, is classified within Federal Supply Class 4520 (Space and Water Heating Equipment) of the Plumbing, Heating, and Waste Disposal group. The manufacturer of record is Chromalox Inc Dba Chromalox Precision Heat and Control, Inc. Government technical data includes 16 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4520-00-281-3666 |
| Primary Part Number | ATU1267 |
| Item Name | Heating Element,electrical,nonim |
| FSC / FSG | 4520 / 45 — Space and Water Heating Equipment |
| Manufacturer | Chromalox Inc Dba Chromalox Precision Heat and Control, Inc |
| Status | ACTIVE |
| Terminal Quantity | 2 |
| Length | 10.750 INCHES NOMINAL IN |
| Voltage in Volts and Current Type | 240.0 AC SINGLE VOLTAGE |
| Body Style | TUBULAR, STEPPED |
| Maximum Wattage Rating in Watts | 675.0 SINGLE VOLTAGE |
| Terminal Length | 0.375 INCHES NOMINAL IN |
| Element Connection Style | STUD TYPE |
| Outside Diameter | 0.375 INCHES NOMINAL IN |
| Nominal Thread Size | 0.190 INCHES STUD IN |
| Heat Quantity | 1 |
| Watt Density Rating | 29.0 PER SQUARE INCH SINGLE VOLTAGE |
| Element Radiation Spectrum | NONINFRARED |
| Material | CHROMIUM AND IRON AND NICKEL SHEATH |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) STUD |
| Thread Quantity | 32.0 PER INCH STUD |
| Element Quantity | 1 |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
NSN 4520-00-281-3666 is a Heating Element,electrical,nonim, manufactured by Chromalox Inc Dba Chromalox Precision Heat and Control, Inc, classified under FSC 4520, Space and Water Heating Equipment. Status: active.
NSN 4520-00-281-3666 has 2 manufacturer part numbers on file: ATU1267 (Chromalox Inc Dba Chromalox Precision Heat and Control, Inc), 777181 (Lockheed Martin Corporation Div Rms - Mitchel Field).
1 possible match (shared part number, not a government interchangeability claim): 4710-01-362-5199. Verify interchangeability with system specifications before substitution.
Key specifications for ATU1267: Terminal Quantity: 2; Length: 10.750 INCHES NOMINAL IN; Voltage in Volts and Current Type: 240.0 AC SINGLE VOLTAGE; Body Style: TUBULAR, STEPPED. 16 specifications are documented in the U.S. Government catalog.
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.