Our crowtail products need some water flow sensor, what we choose to join us crowtail is a G1/4" water flow sensor that consists of magnetic core, rotating impeller, external casing and sensor and a hall-effect sensor. When water flows through the rotor, https://elecena.pl/product/7560148/crowtail-g1-4-water-flow-sensor-2-0 2017-02-01 https://elecena.pl/product/7560148/crowtail-g1-4-water-flow-sensor-2-0 2025-12-17