The 120 Volt Infratech surface mount double regulator comes with two INF input regulators, a deep gang box, and a waterproof cover so you can install it in exposed exterior locations. INF controls are a great option to affect the intensity of your infrared heater. The 120 Volt Infratech surface mount double regulator should be installed directly into the line between the main power source and the heater. This regulator works like a temperature control on an appliance and is heat sensitive.