This is fully submersible heater with unbreakable titanium heating tube, temperature control dial, ON/OFF indicator, and temperature indicator. LCD monitor displays current water temperature. This is a perfect choice for either salt or fresh water system. This heater comes with one year warranty. When selecting the heater for your tank it is a good rule of thumb to dedicate 5W for each gallon of water. For example 30 gallon tank will require 150W heater (30gal x 5W). This is Controller Only.