The CT50 is a Wi-Fi enabled thermostat that allows you to access it from anywhere you have an internet connection. You can also access it via iOS or Android devices via a free application. With advanced features the software knows when you are away from home an automatically turns down the temperature and when you get within a user specified range it turns the temperature back up so the house is comfortable when you arrive. Sleek 7-day programmable thermostat with touchscreen controls. The CT50 works with nearly any HVAC system - including traditional furnaces and heat pumps. The CT50 can control up to 2 stages of heat and 2 stages of cool. The CT50 allows you to program up to 4 independent periods per day. Auto Changeover mode available Includes Wi-Fi unsnap module - allows connection to Wife and/or our cloud services. Open API available to allow you to create your own interface. C wire required for Wi-Fi operation additional minimal annual fee required.