This combo includes our Electric Base Heater, Rubber Water Pan, and Preset Thermostat. It is used to keep waterers from freezing in cold months. Element carries a 1-year guarantee; 100 watts, 115 volts. It is 16″ in diameter and 3 1/4″ in height. Model AEB will keep the water from freezing with temperatures in the single digits in a sheltered area. The AEB is not designed for outdoor use where there is apt to be single-digit temperatures (or colder) with a wind chill.