This is what I'm using this winter in a 5 gallon bucket to prevent freezing. I live in the stinkin' snow belt in Northeast Ohio. Using no artificial heat for anything other than the nipple waterer. Bought this at tractor supply. They had several sizes in stock. Protective seat attached to bottom of heater allows it to sit nicely in the bottom of the bucket without worry of overheating plastic. Bring on the cold and snow!!!