Power Failure Alarm: The siren will alarm when the power supply is cut off until restore power; the warning could be manual muted by on/off switch.
LED Indicaters: The LED indicater can show power out / failure alarm and power condition, convenient to know the power condition.
Drawer-type cell cover design: The drawer-type cell cover can make the change of battery easier.
High voltage resistant design: With the specially design, the siren can work fine even if the power voltage exceeds standard.
Using Method: Firstly place the bottom of the 9 V battery(not included) in the battery compartment according to the positive and negative poles.Then connect the alarm with 220V power and turn on the power switch.