There is a on-off which can switch the metal detector from sound alarm to light alarm, or from light alarm to sound alarm. It fits to work in different environments.
It can be recharged. It needs 4-6 hours for charging. (the charger and rechargeable battery are ordered additional)
The alarm terms is sound and light alarm simultaneously, or vibration and light alarm simultaneously. You can choose the operate terms optionally.
When the low sensitivity on-off is pressed, the metal detector will only alarm when it finds big metal object.