Vision conventional 7 day programmable. For heating and air conditioning systems. Universal thermostat: Compatible with virtually all HVAC systems. Adaptive intelligent recovery (smart response). Menu driven programming. Filter change reminder and low battery indicator. Armchair programming. 4 daily periods. Precise temperature control (+/-1 deg. F.). Large, clear, backlit display 4.5 sq. in. of viewable area. Soft-key controls. Easy installation. Real time clock that keeps time during a power failure. Requires 2 "AA" batteries (not included). Off-white. ENERGY STAR rated.