YTHX9421R5101WW PRESTIGE 2-WIRE IAQ KIT WITH REDLINK TECHNOLOGY RESIDENTIAL OR COMMERCIAL USE 7 DAY PROGRAMMABLE UP TO 4H/2C HEAT PUMP OR UP TO 3H/2C CONVENTIONAL. KIT CONTAINS THX9421R5021WW COLOR TOUCH SCREEN THERMOSTAT, THM5421R1021 EQUIPMENT INTERFACE MODULE, C7089R1013 WIRELESS OUTDOOR SENSOR AND 2 DUCT SENSORS