Honeywell TH3110D1008, PRO 3000 series Digital Non Programmable Single Stage (1H/1C) Dual Powered Thermostat. Provides electronic control of 24 Vac conventional and heat pump systems or 750 mV heating systems. Voltage Rating: 20 to 30 Volt AC/750 Millivolt at 50/60 Hertz Current Rating: 0.02 to 1 Amp (Heat/Cool) Size 5-3/8" W x 1-1/4" D x 3-13/16" H Terminal Designations R Rc W Y G O B C Non-programable digital thermostat with backlit display that is easy to read in various lighting conditions. Maintains a precise consistent comfort to the highest level of accuracy (+/- 1°F). Basic operation with an easy to use switch to select heat or cool mode and fan operation. 2 AA batteries required.