This programmable low voltage thermostat is suitable for use with
forced hot air heating systems with central air conditioning. The feature making this thermostat particularly unique is that it will automatically switch between heating and cooling as needed. You may program up to four settings per day, with each day being programmed differently if desired. It will retain the settings in memory even during a power outage, eliminating the need to re-program the thermostat. Suitable for 2, 3, 4 or 5 wire applications. 3.8" (97 mm) wide x 4.9" (125.5 mm) high x 1.0" (26 mm) deep.