Honeywell Thermostat RTH8500D is an advanced smart thermostat with Wi-Fi connectivity, allowing you to control your home's temperature from anywhere using your smartphone or tablet. The large, easy-to-read display shows the current temperature, humidity, and time, and the programmable settings let you customize your heating and cooling schedule. The RTH8500D also has several energy-saving features, such as the Auto Changeover function, which automatically switches between heating and cooling modes to maintain your desired temperature.