RF equipment interface module controls up to 3 heat/2 cool (heat pump) or up to 2 heat/2 cool (conventional) system when used with wireless FocusPRO thermostat. Easily relocate thermostat or upgrade equipment without running new wires using this module and a wireless FocusPRO® thermostat. Powered by RedLINK™ reliability; no interference with other wireless devices in the home. Works with TH6320R1004 or TH5320R1002 Wireless FocusPRO® thermostats. Input for return air sensor. Quick-connect terminal blocks. LEDs for power and system status. Use with gas, oil, electric, heat pump, forced warm air, hot water, steam or gravity. Dimensions: 8-1/8 inch high x 8 inch wide x 1-7/8 inch deep (206mm high x 203mm wide x 47mm deep). Equipment interface module is also available in kits. Electrical ratings: 18- to 30-volt (AC), 50/60 Hz. Operating humidity range (% Relative Humidity-RH): 5 to 95% RH, non-condensing. Operating temperature range: -40F to 165F (-40C to 73.9C). Color: gray. Parts needed for operation (not included): TH6320R1004 or TH5320R1002 Wireless FocusPRO® Thermostat.