PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

PT109Thermometer,self-Indicating

Sigma Products & Mfg · NSN 6685-00-143-4746 · FSC 6685 · No Item Name Available
Verified by PartsTable
NSN 6685-00-143-4746 — this item is cataloged by the U.S. Government under National Stock Number 6685-00-143-4746. Primary manufacturer part number: PT109.
Features
  • Thermometer,self-Indicating — FSC 6685
  • Securing Device Type: RINGRING
  • Scale Type: ETCHED STEMETCHED STEM
  • Scale Smallest Increment: 2.0 DEG FAHRENHEIT2.0 DEG FAHRENHEIT
  • Material: BRASS METER CASE
  • Design Type: FLUCTUATINGFLUCTUATING
  • Style Designator: CUP CASE
  • Actuating Medium: MERCURYMERCURY
Applications
  • Applications requiring Brass Meter Case construction
General Description

The Thermometer,self-Indicating, cataloged under National Stock Number 6685-00-143-4746, is classified within Federal Supply Class 6685 (No Item Name Available) of the Instruments and Laboratory Equipment group. The primary manufacturer of record is Sigma Products & Mfg. Government technical data includes 8 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 3 commercial cross-references from 3 manufacturers, enabling identification through both NSN and commercial part number lookups. 12 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN6685-00-143-4746
Primary Part NumberPT109
Item NameThermometer,self-Indicating
FSC / FSG6685 / 66 — No Item Name Available
ManufacturerSigma Products & Mfg
StatusACTIVE
Securing Device TypeRINGRING
Scale TypeETCHED STEMETCHED STEM
Scale Smallest Increment2.0 DEG FAHRENHEIT2.0 DEG FAHRENHEIT
MaterialBRASS METER CASE
Design TypeFLUCTUATINGFLUCTUATING
Style DesignatorCUP CASE
Actuating MediumMERCURYMERCURY
Scale Measurement Range+140.000 TO 220.000 DEG FAHRENHEIT+140.000 TO 220.000 DEG FAHRENHEIT
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 12
3439-00-223-3758PT109 INTERCHANGEABLE
Desoldering Tool
Edsyn Inc
5360-00-383-918107-852166 INTERCHANGEABLE
Spring,helical,compression
Tvh Parts Co.
5325-00-818-252721810 INTERCHANGEABLE
Ring,retaining
Winchester Interconnect Corporation Dba Winchester Interconnect Div Winchester Interconnect
5950-00-984-7865 INTERCHANGEABLE
Transformer,power
3110-01-007-762621810 INTERCHANGEABLE
Ball,bearing
Mason Electric Co. Dba Mason Controls
5985-01-036-6214218-10 INTERCHANGEABLE
Attenuator,fixed
Cinch Connectivity Solutions Inc
5310-01-049-0471NW21810 INTERCHANGEABLE
Nut,plain,wing
Tld Wollard Llc
5961-01-169-6507 INTERCHANGEABLE
Transistor
5950-01-210-106921810 INTERCHANGEABLE
Reactor
Westerbeke Corporation
4720-01-374-413621810 INTERCHANGEABLE
Hose,preformed
Gates Corporation
Cross-Reference Index
Part NumberManufacturer
PT109 PRIMARY Sigma Products & Mfg (USA)
PT109 Psg Controls, Inc. (USA)
21810 Tycos Instruments Inc a Welch Allyn Co (USA)
Related Parts
3439-00-223-3758INTERCHANGEABLE
DESOLDERING TOOL
PT109
5360-00-383-9181INTERCHANGEABLE
SPRING,HELICAL,COMPRESSION
07-852166
5325-00-818-2527INTERCHANGEABLE
RING,RETAINING
21810
5950-00-984-7865INTERCHANGEABLE
TRANSFORMER,POWER
3110-01-007-7626INTERCHANGEABLE
BALL,BEARING
21810
5985-01-036-6214INTERCHANGEABLE
ATTENUATOR,FIXED
218-10
5310-01-049-0471INTERCHANGEABLE
NUT,PLAIN,WING
NW21810
5961-01-169-6507INTERCHANGEABLE
TRANSISTOR
5950-01-210-1069INTERCHANGEABLE
REACTOR
21810
4720-01-374-4136INTERCHANGEABLE
HOSE,PREFORMED
21810
4130-01-395-9333INTERCHANGEABLE
RECOVERY TOOL,REFRIGERANT
5945-01-499-8516INTERCHANGEABLE
RELAY,HYBRID
21-810

Frequently Asked Questions

What is NSN 6685-00-143-4746?

NSN 6685-00-143-4746 is a Thermometer,self-Indicating, manufactured by Sigma Products & Mfg, classified under FSC 6685 (No Item Name Available). Status: active.

What are the part numbers for NSN 6685-00-143-4746?

NSN 6685-00-143-4746 has 3 cross-referenced part numbers: PT109 (Sigma Products & Mfg), PT109 (Psg Controls, Inc.), 21810 (Tycos Instruments Inc a Welch Allyn Co).

What NSN replaces 6685-00-143-4746?

There are 12 known substitutes for 6685-00-143-4746: 3439-00-223-3758, 5360-00-383-9181, 5325-00-818-2527 and 9 more. Verify interchangeability with system specifications before substitution.

What are the specifications of PT109?

Key specifications for PT109: Part Name Assigned by Controlling Agency: THERMOMETER SELF-INTHERMOMETER SELF-IN; Securing Device Type: RINGRING; Scale Type: ETCHED STEMETCHED STEM; Scale Smallest Increment: 2.0 DEG FAHRENHEIT2.0 DEG FAHRENHEIT. 10 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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