... in the pipe, the magnet will detect the water flow and make the reed switch close or open.Light weight ... ,easy installation ,long lifetime ,ROHS and CE approvals .1.Mass production ,competitive price .2.Tap water or oil applied ,without ... liquid corrosion resistance .5.Switch contact start value for fliquid flow :3L/Min -15L/MinTechnical Datasheet Caliber Size22mmMax Switch Rating70W 100WMax ...