PRO1® Programmable Thermostat, 24 VAC, 50/60 Hz Frequency, Programmability: 5-1-1, 7 day Program, Changeover: Auto, Battery, Hardwired Power Source, 2 Heat/2 Cool Stages, Switch Position: AUTO-HEAT-COOL-OFF-EMERGENCY (System), AUTO-ON (Fan), 13 sq-in Touchscreen LCD Display, 0.2 to 2 deg F Differential, 44 to 90 deg F Settings, +/-1 deg F Accuracy, Wall, Junction Box Mounting, Terminal Designation: RC, RH, C, O, B, G, Y, Y2, W/E, W2, White, Dimensions: 4.4 in H x 4.7 in W x 1.1 in D