Digital Hall Magnetic Sensor Module (KY-035 3pin, 3144233)
$29.48
$44.21
Hall Effect Sensors are devices which are activated by an external magnetic field. The output signal from a Hall effect sensor is the function of magnetic field density around the device. When the magnetic flux density around the sensor exceeds a certain pre-set threshold, the sensor detects it and generates an output voltage called the Hall Voltage.
Arduino