Basic Thermostats for low voltage control of single-stage heating, cooling or heating-cooling systems.
Snap acting bimetal switch uses no mercury and does not require leveling
Honeywell Low Voltage Thermostat, Series: T812A, Non-Programmable Thermostat, SPST Switch Action, Snap Action Switch, Terminal Designations: W, R, Bi-Metal Sensor, 1 Stage, 5 to 90 % Humidity, 20 to 30 VAC, Square Mounting, Premier White, 3-1/8 in W x 7/8 in D x 3-1/8 in H