Check the listing for details. Hi-Limit/Temp Sensor Kit for Watkins Hot Springs Spa No-Fault Heater 39525/39530. Condition: New. Listed at 49.95 USD. Hi-Limit/Temp Sensor Kit for Watkins Hot Springs Spa No-Fault Heater 39525/39530 Our premium replacement High-Limit & Temperature Sensor Kit fits Watkins Hot Spring® No-Fault heaters with 2 threaded sensor ports as shown. 1/2" threaded thermistor Hi-limit sensor (smaller port) 5/8" threaded thermistor Temp sensor (larger port) 36" cables O-rings and connector plugs includedMolex to AMP plug adaptor cables included Product notes: 100% Guaranteed to equal or surpass the reliability and longevity of the OEM sensors. Always replace both sensors together. Associated part numbers are 39525, 39530. Molex plugs fit 2002+ model years (parts 39525, 39530). Included Adapter Cable Set converts Molex to larger AMP style plugs to fit pre-2002 models (parts 38415, 38416).