This manual non-programmable line voltage thermostat is compatible with a variety of heating systems and provides simple operation with its bimetal temperature sensor. It is a 4-wire thermostat that offers double-line break for easy installation. The temperature range is 40 degreeF to 80 degreeF (4 degreeC to 27 degreeC) for heat only. The power requirements are 2640W @ 120 Vac, 22A resistive; 5280W @ 240 Vac, 22A resistive; 5263W @ 277 Vac, 19A resistive, and it can be used to control a single electric baseboard heater or multiple electric heaters. If replacing a control with mercury, proper disposal instructions should be followed.