The Thermowell, cataloged under National Stock Number 6685-01-522-7218, 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 Rdf Corporation. Government technical data includes 2 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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.
| Parameter | Value |
|---|---|
| NSN | 6685-01-522-7218 |
| Primary Part Number | FB-8.25-6.25-0-B-R150-1 |
| Item Name | Thermowell |
| FSC / FSG | 6685 / 66 — Pressure, Temperature, and Humidity Measuring and Controlling Instruments |
| Manufacturer | Rdf Corporation |
| Status | ACTIVE |
| Material Document and Classification | 304 ASSN STD SINGLE MATERIAL RESPONSE |
| Material | STEEL COMP 304 |
| 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 |
|---|---|
| FB-8.25-6.25-0-B-R150-1 PRIMARY | Rdf Corporation (USA) |
| Reference | Meaning |
|---|---|
| FB8.25-6.25OB150-1 | 5/9 Secondary reference Rdf Corporation |
| 53755 | D/9 Drawing number reference only Rdf Corporation |
NSN 6685-01-522-7218 is a Thermowell, manufactured by Rdf Corporation, classified under FSC 6685, Pressure, Temperature, and Humidity Measuring and Controlling Instruments. Status: active.
NSN 6685-01-522-7218 has 1 manufacturer part number on file: FB-8.25-6.25-0-B-R150-1 (Rdf Corporation).
1 possible match (shared part number, not a government interchangeability claim): 2590-01-581-5487. Verify interchangeability with system specifications before substitution.
Key specifications for FB-8.25-6.25-0-B-R150-1: Material Document and Classification: 304 ASSN STD SINGLE MATERIAL RESPONSE; Special Features: 8.25 INCH STEM LENGTH; 6.25 INCH INSERTION LENGTH; 0 LAG LENGTH; RAISED FACE IN; Material: STEEL COMP 304. 2 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.