It is operated by AC 120V/60Hz with DC9V battery backup, and warns you when the battery is low.
In order not to disturb your rest, the product designed function of silence.
With the increase of working time the alarm detection signal will be decayed, when attenuate to the certain value, the alarm will send a fault signal, you must replace the product immediately.
Product design of the test function by pressing the test button, used to test the product is working normal.
FEATURES:
Photoelectric smoke alarm device;
Certification test for UL217;
AC120V/60Hz with DC9V battery backup, and low battery warning