Water flow sensor consists of a plastic valve body, a water rotor, and a hall-effect sensor. When water flows through the rotor, rotor rolls. Its speed changes with different rate of flow. The hall-effect sensor outputs the corresponding pulse signal. This one is suitable to detect flow in water dispenser or coffee machine. We have a comprehensive line of water flow sensors in different diameters. Check them out to find the one that meets your need most. Features Compact, Easy to Install High Sealing Performance High Quality Hall Effect Sensor RoHS Compliant TypeDimensions(DN)Working VoltageFlow Rate RangeLengthMale & FemaleLength of ThreadMaterial YF-B1 DN15 5V~15V(DC) 1~25L/min 44mm Double Male 10mm Copper YF-B2 DN15 5V~15V(DC) 1~25L/min 50mm Male in Female out 10mm Copper YF-B3 DN15 5V~15V(DC) 1~25L/min 66mm Double Male 18mm Copper YF-B4 DN15 5V~15V(DC) 1~25L/min 66mm Male in Female out 10mm Copper YF-B5 DN20 5V~15V(DC) 1~30L/min 50mm Double Male 10mm Copper YF-B6 DN20 5V~15V(DC) 1~30L/min 60mm Double Male 11mm Copper YF-B7 DN15 5V~15V(DC) 1~25L/min 66mm Double Male 10mm Copper G1&2 DN15 5V~24V(DC) 1~30L/min Double Male Plastic G3&4 DN20 5V~24V(DC) 1~60L/min Double Male Plastic G1&2 DN15 5V~24V(DC) 1~30L/min 60mm Double Male 13mm Plastic G1&8 - 5V~24V(DC) 0.3~6L/min - - - Plastic M11*1.25 - 5V~24V(DC) 0.3~6L/min - - - Plastic