Standard Features - Weekday/Weekend Programming One program for the weekdays and a separate program for the weekends with 4 program periods per day - Filter change reminder Keep your heating/cooling system operating at peak performance - Easy to Use Basic operation keeps programming easy - Backlit display - Precise temperature control of +/-1 F to maximize comfort - Works with low volt heating/cooling systems including millivolt & single-stage heat pumps without auxiliary heat - Does not work with heat pump systems with back-up heat or electric baseboard heat (120-240V) - 1 Year Limited Warranty