The Thermowell, cataloged under National Stock Number 6685-01-021-2599, is classified within Federal Supply Class 6685 (Pressure, Temperature, and Humidity Measuring and Controlling Instruments) of the Instruments and Laboratory Equipment group. Government technical data includes 1 specification, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 3 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 6685-01-021-2599 |
| Item Name | Thermowell |
| FSC / FSG | 6685 / 66 — Pressure, Temperature, and Humidity Measuring and Controlling Instruments |
| Status | ACTIVE |
| Material | NICKEL ALLOY |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | Possible hazard — SDS may be required (DLA HMIC P) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| 11725GR2 | 5/1 Secondary reference U.S. Government activity |
| 5443-2 | 3/1 Design control — primary reference U.S. Government activity |
NSN 6685-01-021-2599 is a Thermowell, classified under FSC 6685, Pressure, Temperature, and Humidity Measuring and Controlling Instruments. Status: active.
3 possible matches (shared part number, not a government interchangeability claim): 6150-01-520-3608, 5995-01-550-9675, 5340-01-630-7510. Verify interchangeability with system specifications before substitution.
Key specifications for 6685-01-021-2599: End Item Identification: NUCLEAR REACTORS PROGRAM; Material: NICKEL ALLOY. 1 specification is 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.