Features 【How it Works】In the case of normal water inflow, the lower float switch starts and the upper float switch stops. When draining, the upper float switch starts and the lower float switch stops working 【Action Range】The action range of the two floats of the liquid level sensor is 10mm; and If you want to increase the control range, you can combine two float switches to work together 【Wide Application】This vertical water float switches has a wide range of application, which can be used to control the liquid level of the water tank, pool, sink, fish tank, etc., or to make the upper and lower alarm switch for liquid level monitoring 【Warm Prompt】The water level controller cannot directly control solenoid valves or high-power relays, AC contactors, etc. A small relay(like HH54P) is needed for transition 【Sincere Promise】We have been always doing our best to provide the best service and shopping experience, so please feel free to turn to us if you have any problems about our products Specification: Voltage:DC 0~110V Material:304 Stainless Steel Size(Floating Body Length):(Optional) 100mm / 3.94in  150mm / 5.91in 200mm / 7.87in 250mm / 9.84in Package List: 1 x Double Ball Float Switch Package List