Switching voltage (Max): 110VDC Switching current (Max): 0.5A Transport current (Max): 1A Contractual resistance (max.): 100 OHM Temperature rating: -20 ~ + 80 ° C A float switch is a device used to detect the level of liquid in a tank. It can activate a pump, indicator, alarm or other device. Use them with hydroponics, salt water tank, fresh water tank, gardening, aquariums for motorized head control, bowls for pets, aquariums, filtration, heating or any other project in progress. Does not contain mercury.