PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

125-203Thermowell

Rochester Sensors, Llc · NSN 6685-00-407-0670 · FSC 6685 · No Item Name Available
Verified by PartsTable
NSN 6685-00-407-0670 — this item is cataloged by the U.S. Government under National Stock Number 6685-00-407-0670. Primary manufacturer part number: 125-203.
Features
  • Thermowell — FSC 6685
  • Material: COPPER ALLOY
  • Bulb Tip Outside Diameter: 0.500 INCHES NOMINAL IN
  • External Thread Size: 3/4 IN. NPT3/4 IN. NPT IN
  • Bulb Tip Length: 2.380 INCHES NOMINAL IN
  • Style Designator: THREADED STRAIGHT SHANK
  • Internal Thread Size: 3/4 IN.-28 ALL BORES IN
  • 4 verified cross-references
Applications
  • Applications requiring Copper Alloy construction
General Description

The Thermowell, cataloged under National Stock Number 6685-00-407-0670, is classified within Federal Supply Class 6685 (No Item Name Available) of the Instruments and Laboratory Equipment group. The primary manufacturer of record is Rochester Sensors, Llc. Government technical data includes 6 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 4 commercial cross-references from 4 manufacturers, enabling identification through both NSN and commercial part number lookups. 5 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN6685-00-407-0670
Primary Part Number125-203
Item NameThermowell
FSC / FSG6685 / 66 — No Item Name Available
ManufacturerRochester Sensors, Llc
StatusACTIVE
MaterialCOPPER ALLOY
Bulb Tip Outside Diameter0.500 INCHES NOMINAL IN
External Thread Size3/4 IN. NPT3/4 IN. NPT IN
Bulb Tip Length2.380 INCHES NOMINAL IN
Style DesignatorTHREADED STRAIGHT SHANK
Internal Thread Size3/4 IN.-28 ALL BORES IN
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 5
1560-00-997-250811281 INTERCHANGEABLE
Tube Assembly,bleed
Fmh Aerospace Corp.
6105-01-246-000897768 INTERCHANGEABLE
Adapter,motor to Gearcase
Scientific Atlanta Inc
5315-01-249-0553125203 INTERCHANGEABLE
Pin,straight,headless
L3harris Technologies, Inc Div Space & Airborne Systems
5331-01-463-9932125203 INTERCHANGEABLE
O-Ring
Brp Us Inc
5310-01-502-17509776-8 INTERCHANGEABLE
Washer,flat
Amphenol Corp Div Amphenol Aerospace Operations
Cross-Reference Index
Part NumberManufacturer
97768 Solartron Electronics Inc Weston Instruments Div (USA)
125-203 PRIMARY Rochester Sensors, Llc (USA)
11660668 U S Army Tank Automotive Command Amsta-Im-Mm (USA)
11660668 Fnss Savunma Sistemleri Anonim Sirketi (TUR)
Related Parts
1560-00-997-2508INTERCHANGEABLE
TUBE ASSEMBLY,BLEED
11281
6105-01-246-0008INTERCHANGEABLE
ADAPTER,MOTOR TO GEARCASE
97768
5315-01-249-0553INTERCHANGEABLE
PIN,STRAIGHT,HEADLESS
125203
5331-01-463-9932INTERCHANGEABLE
O-RING
125203
5310-01-502-1750INTERCHANGEABLE
WASHER,FLAT
9776-8

Frequently Asked Questions

What is NSN 6685-00-407-0670?

NSN 6685-00-407-0670 is a Thermowell, manufactured by Rochester Sensors, Llc, classified under FSC 6685 (No Item Name Available). Status: active.

What are the part numbers for NSN 6685-00-407-0670?

NSN 6685-00-407-0670 has 4 cross-referenced part numbers: 97768 (Solartron Electronics Inc Weston Instruments Div), 125-203 (Rochester Sensors, Llc), 11660668 (U S Army Tank Automotive Command Amsta-Im-Mm), 11660668 (Fnss Savunma Sistemleri Anonim Sirketi).

What NSN replaces 6685-00-407-0670?

There are 5 known substitutes for 6685-00-407-0670: 1560-00-997-2508, 6105-01-246-0008, 5315-01-249-0553 and 2 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 125-203?

Key specifications for 125-203: Material: COPPER ALLOY; Bulb Tip Outside Diameter: 0.500 INCHES NOMINAL IN; External Thread Size: 3/4 IN. NPT3/4 IN. NPT IN; Bulb Tip Length: 2.380 INCHES NOMINAL IN. 7 total characteristics are documented in the Federal Logistics Information System.

Validated with multiple authoritative sources, including Government, OEM, and Certified sources.
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