The exact depth where the water temperature changes dramatically from warmer to colder is known as the thermocline, it is also known to hold the most aggressive fish when they become suspended. This unique thermometer gives you a reading at the thermoclines to improve your chances of landing big fish. Virtually unbreakable and fully waterproof, this temperature sensing system uses a remote sensor mounted to 50 feet of cable to determine the temperature at different depths. The LCD readout on the cable reel displays temperatures accurate to 0.5° F and takes only a few seconds to record changes in temperature.