Advantage: 1.Suitable for many places. 2.Strong 85 decibel alert. 3.7-year life carbon monoxide detector. 4.Big Test button allows you to test the detector. 5.The LED lights show three different instructions with color.(the green indicates normal operation, the red indicates an alarm state, and the yellow indicates a fault) 6.It has a low battery warning to remind you when to replace the battery.    Attention: 1.This CO alarm is designed for indoor use only. DO not expose to rain or moisture. DO not knock or drop the detector. DO not open or tamper with the alarm as this could cause malfunction. 2.The alarm will not protect against the risk of carbon monoxide poisoning when the battery has drained. 3.Installation of the alarm should not be used as a substitute for proper installation, use and maintenance of fuel burning appliances including appropriate ventilation and exhaust systems.  Specification: 1.Type of apparatus: Type B 2.Power Supply: DC 3V(2pcs alkaline battery) 3.Recommend battery type: GP  GN15A / Raymax  LR6 4.Sensor Type: Electrochemical 5.Product life: 7 years after manufacture 6.Sensitivity Setting: Conforms to EN 50291-1:2010+A1:2012 standard.  30PPM     Without alarm before 120 minutes   50PPM     Between 60 to 90 minutes   100PPM    Between 10 to 40 minutes   300PPM    Less than 3 minutes 7.Standby Current: <20A (average) 8.Alarm Current: <25mA (average) 9.Operation Ambient Condition: -10~+40?, 30~95% non-condensing 10.Storage/Transport Ambient Condition: -20~+50?, 10~95% non-condensing 11.Alarm sound : =85DB at 100cm @3.20.5KHz pulsing alarm 12.Low Battery warning silence: about 9 hours