1、By measuring the carbon monoxide gas content and smoke concentration in the air, an alarm will be issued when the industry standard limit is reached. 2、Send out an audible and visual alarm greater than 85dB when alarming, push APP alarm information at the same time and dial the cloud alarm phone (the preset telephone number of the alarm receiver). 3、The cloud alarm log allows users to query historical alarms anytime and anywhere, more convenient to use, bring you more advantages. 4、Mainly used in homes, warehouses, enterprises, schools, hospitals, restaurants and other places that can cause gas leaks and fires. 5、2pcs CR123A lithium batteries are used, can maintain a standby time of two years and reduce the frequency of battery replacement. 1 x Carbon Monoxide Alarm2 x Screw 2 x Expansion Tube 1 x Manual  Item Type: Carbon Monoxide AlarmMaterial: ABS Battery Model: 2pcs CR123A + 1pc built-in lithium battery 1000mAhAlarm Concentration: 100PPMStandby Current: <25uAAlarm Current: 50mAWorking Environment: +5℃ to +40℃Installation Method: Wall or ceiling