CH7100 High Resolution Heat Pump Thermostats are multi-functional devices that offer a simple-to-use color touch screen user interface. This stand-alone digital heat pump thermostat is designed to program and configure temperature control of a wide range of heating and cooling equipment in both residential and commercial applications. Item No.: CH7100 A c-wire is required for all systems Works with two stages of heating and two stages of cooling (2H/2C) Works with Heat Only and Cool Only system  Works with Heat Pump (With or Without Aux) Works with Amazon Alexa, Google Assistant Remotely control your home comfort from your smartphone Using the free mobile app for Android and iOS devices. 4.3 inch TFT Capacitive Touchscreen Display