Wrap-On 18800 Pre-Set Thermostat 1800W 15A When plugged into a 120 VAC electrical outlet, thermostat will automatically turn the power on and off to any device plugged into it. Will turn power on when air temperature drops below 35F and turn power off when the temperature exceeds 45F. The Preset Thermostat can be used with self-regulating type heating cables and many electrical devices such as heat lamps, stock tank heaters and pond heaters. Simply unplug the heating cable, plug in the Preset Thermostat, and then insert the heating cable plug into the thermostat. Made in USA