The Tank Model (TM) A vented tank heater that fits a 10 gallon aquarium tank. Ideal for reptiles, brooders and terrariums. It is 11 inches wide and 20.5 inches long and is rated at 45 watts. For additional safety measures, the Sweeter Heater has a snap-action thermal control to insure heaters turn off automatically when heat is not allowed to escape. Side mount cord only.