High quality of PP, Environment Friendly and nontoxic. Key floating switch control that can adjust the level of a bucket, a tank or a well. In filling water state, use "Red and Yellow " wire with these contact the regulator close when down, opens when up. In empting water state, use "Red and Green" wire with these contacts the regulator, open when up, close when down . Avoid insufficient water sources from damaging pump device Be widely used for home pool, factory pool, also used for Oil tank, a