Using the principle of float, the water level controls the inlet and outlet water switch to achieve constant water level effect, keep enough water and always clean. Always float in the water when the water rises, the floats follow the rise. And the rod driven by the rise also rises. Large water flow, high efficiency, good sealing. Works great for waterers, humidifiers, fountains, aquariums, ponds, chicken/dog/horse/livestock waterers, etc. Rubber seal ensures the equipment is waterproof and leak-free, and you can easily adjust the floating arm. Items Description: Using the principle of floating water level, the switch controls the incoming and outgoing water to achieve a constant water level effect, keeping water sufficient and always clean. Floats immobile in water: When the water rises, the floats follow the rise. And the rod pushed by the lift also goes up. Large water flow, high efficiency, good sealing. Works great for waterers, humidifiers, fountains, aquariums, ponds,