The API tank heater will keep a tank-with or without drinkers-from freezing in even the most severe winter weather. Only a pair of pliers is required to securely with the simple clamp device. Wariable temperature adjustment is enclosed in a weatherproof casing at top of unit, and the 120 VAC stainless steel heating element is sealed and non-corrosive in any water. Unit is 24" high and 21" long. 1500 watts. Wt. 10 lbs.