This King ESP230 series programmable thermostat took years to develop and has become one of our most popular models. Backlighting of the large LCD digital screen makes for easy viewing even across a room. 2 simple buttons control the temperature (up or down) while all programming buttons are conveniently hidden underneath the front cover, protected from wandering, unauthorized fingers. Programming allows even temperature control and potential heating cost savings of up to 15%. Built-in snap action relay. Electronically anticipated. 3 wire installation. Meets most energy codes. Temperature range: 44 - 95°F. 208/240-Volts, 22 Amp.