Amazon.com: Thermocouple 20 gauge. 72"-long, fiberglass-insulated duplex lead wire with welded tip. With miniature plug. Not for liquid immersion. : Industrial & Scientific
AS ONE 1-9930-28 DJ-K-BL-100m Coated Thermocouple (K Thermocouple: Duplex)
Thermocouple technical reference information
Duplex Thermocouple with 2 Elements - China Duplex Thermocouple, K Type Thermocouple | Made-in-China.com
New Pyromation Type J Duplex Thermocouple, 3/16" Dia. 82" Long, JJ39E-82-00-4MC | eBay
K Type Thermocouple Duplex Wire (AWG 24/20) :: OMEGA Engineering