Low Voltage Thermostat, 24V AC, Heat and Cool, 2 1/8 in Overall Depth, 5 3/4 in Overall Height, 7 5/8 in Overall Width, Number of Cooling Stages - Conventional System 1, Number of Cooling Stages - Heat Pump System 1, Number of Heating Stages - Conventional System 1, Number of Heating Stages - Heat Pump System 1, Maximum Control Temperature 90 Degrees F, Minimum Control Temperature 45 Degrees F