Honeywell 7 Day Flexible Programmable Thermostat. It offers 7-day, 5-2 day, or one-week programming, compatible with most systems. The extra-large backlit display clearly shows the current room temperature and set point temperature. It learns your heating/cooling cycle times to deliver the right temperature efficiently. With auto change from heat to cool, it ensures comfortable indoor conditions year-round. Change reminders for filters and low batteries help maintain optimal performance. Temporary and permanent hold settings provide flexibility in temperature control. The real-time clock automatically adjusts for daylight, saving time. The program is retained in memory during power outages. It features a 12 or 24-hour time display, fahrenheit or celsius temperature display, short cycle protection, and fan operation with on/auto/circulate settings. Includes Honeywell standard, connector S16, mounting hardware, and quick install guide. Requires 2 "AA" batteries (not included).