Description: This is a small device called a reed switch. When the device is exposed to a magnetic field, the two ferrous materials inside the switch pull together and the switch closes. When the magnetic field is removed, the reeds separate and the switch opens. This makes for a great non-contact switch. This switch can carry up to 1.2A.
Based on 1 ratings:
I bought 5 of these and none of them worked all the time. Some did not wok at all, staying closed after the magnet was removed. Most worked some of the times. These will not work if the magnet does not stop at the switch. If the magnet goes by the switch without stopping. you get unreliable results.