Plug your appliance into the hot weather Thermo Cube and plug it into the wall. When the temperature rises above 120 the Thermo Cube will turn your appliance ON. When the temperature drops below 100 it will turn your appliance OFF. Each unit has two receptacles for use with more than one device. Can operate loads up to 1800 Watts, 15 Amps, 120VAC. Also available in a 78 ON/70 OFF version.This hot-weather model Thermo Cube is ideal for use with window fans, exhaust fans, ventilators, attic fans or any other air-exchange devices. Automating these devices is crucial if you have plants or animals that are sensitive to heat. You can even use the Thermo Cube with a strobe light to create an "Overheating Warning" system that can be seen by neighboring homes or buildings. Recommended for use with GFCI outlets.