LX Series Thermostat RF Module, 2-Way Wireless Communication, Links Wireless Sensors and Accessories to the Thermostat, Frequency Hopper to Avoid Interference, Compatible with These Thermostats:S1-THSU21P1, S1-THSU32P7, S1-THSU32HP7, S1-TBSU22HN, S1-TBSU32P7, S1-TBSU32HP7, Color:White, Weight:2.1oz, Made In China