Honeywell RTH2510B1018/E1 7 Day Programmable Thermostat

7 day thermostat allows you to program each day differently if desired up to 4 periods per day. Program each day differently - up to 4 periods per day. Energy savings - program to save up to 33 percent on annual heating and cooling costs (if used as directed. Savings may vary depending on geographic region and usage). Basic operation keeps programming simple. Back light display. Early start function; precise temperature control of (+/- 1-degree f) for maximum comfort. Display options - degree c or degree f temperature - 12 or 24 hour clock. Compatible with heating and cooling plus heat pump systems. Does not work with electric baseboard heat (120-240v) and multi-stage heating/cooling systems.