The Hall Switch Click Board™ is a magnetic field activated dual-relay Click Board™. Hall Switch Click Board™ has two high-quality relays, which are activated by the Hall-effect sensor: when the north pole magnetic field is introduced to the sensor, one of the relays will be activated; when the south pole magnetic field is introduced to the sensor, the other relay will be activated. Two high-quality compact relays allow switching of high voltages - up to 220V, so they can cut or establish a connection on the mains side of the circuit.