10K IMMERSION TEMPERATURE SENSOR. The immersion sensor is a waterproof device for measuring the temperature of fluids in a pipe. It features a 304 stainless steel probe and a brass WEL-B thermowell.The well screws into the customer-supplied 1/2'' NPT saddle (or Thredolet® fitting) in the pipe.The sensor fits securely into the thermowell via a brass 1/8'' NPT fitting.The sensor is accurate to ± 0.36ºF (0.2ºC) and has a sensing range of 10ºF to 168ºF. It comes with 8' of 24 AWG wire Dimensions:Thermowell: 5.125''; Sensor in well: 6.5''