Horstmann Drt1 is a digital thermostat that can replace most common indoor residential thermostats and is designed to be used with electric, gas, or oil heating systems. It has a simple and quick installation process that requires only a few tools. The Drt1 features an LCD that shows the current room temperature, the set temperature, and the heater status. It also has a simplified temperature adjustment system that makes it easy to set the desired temperature. Additionally, the Drt1 has a low battery operation mode that will alert the user when the batteries need to be replaced.