The Thermocouple,heating Element, cataloged under National Stock Number 6685-01-503-6404, is classified within Federal Supply Class 6685 (Pressure, Temperature, and Humidity Measuring and Controlling Instruments) of the Instruments and Laboratory Equipment group. The manufacturer of record is Chromalox Inc. Government technical data includes 3 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 6685-01-503-6404 |
| Primary Part Number | 309-117317-025 |
| Item Name | Thermocouple,heating Element |
| FSC / FSG | 6685 / 66 — Pressure, Temperature, and Humidity Measuring and Controlling Instruments |
| Manufacturer | Chromalox Inc |
| Status | ACTIVE |
| Mounting Location | INSIDE METER CASE |
| Material | STEEL CORROSION RESISTING OVERALL |
| Terminal Type and Quantity | 2 WIRE LEAD |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | Possible hazard — SDS may be required (DLA HMIC P) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| 155-072818-002 REV 2 ITEM 11 | Chromalox Inc (USA) |
| 309-117317-025 PRIMARY | Chromalox Inc (USA) |
| Reference | Meaning |
|---|---|
| 155-072818-002 | D/9 Drawing number reference only Chromalox Inc |
NSN 6685-01-503-6404 is a Thermocouple,heating Element, manufactured by Chromalox Inc, classified under FSC 6685, Pressure, Temperature, and Humidity Measuring and Controlling Instruments. Status: active.
NSN 6685-01-503-6404 has 2 manufacturer part numbers on file: 155-072818-002 REV 2 ITEM 11 (Chromalox Inc), 309-117317-025 (Chromalox Inc).
Key specifications for 309-117317-025: Mounting Location: INSIDE METER CASE; End Item Identification: HEATER LUBE OIL; Material: STEEL CORROSION RESISTING OVERALL; Terminal Type and Quantity: 2 WIRE LEAD. 3 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.