Characteristics:Alarm carbon monoxideIf the device detects carbon monoxide gas concentrations greater than 100 ppm, an alarm sounds and the buzzer sounds four "di" times every 5 seconds. The red light flashes and continues the alarm. Please open the windows and doors. Then call your emergency services.Fire -If the device detects a smoke concentration greater than 0.1% db / m, an alarm is triggered, the blue light flashes quickly and the buzzer continues the alarm.Specification:Power supply: 3 * 1.5V AA batteryStatic Current: Alarm current: Alarm voice: light / sound promptSensor: Electrochemical carbon monoxide sensor and infrared light barrierTemperature: 0 50 -50Relative humidity: 10-95%Carbon monoxide sensor detects concentration: 000-999 PPMSmoke sensor sensitive: 0.1% db / m-9.9% db / mAlarm display: LCD display, light / sound promptBattery capacity: low battery alarmDimensions: 104 * 39mmPackage list/per Set.1 * Combination smoke and carbon monoxide alarm1 * set of mounting screws1 * User Manual (English)Attentions:1. Read the instruction manual carefully and keep it for future reference.2. This is a carbon monoxide and smoke alarm that cannot detect flammable gases (such as liquefied petroleum gas, natural gas, methane, etc.).3. 2 in 1 Combination smoke detector and carbon monoxide detector4.LCD display concentration PPM5. High-precision electrochemical sensor and infrared light barrier6. Easy installation, no need to debug7. Planned maintenance: surface cleaning every month, specialist inspection every six months.8. It is highly recommended that you test the alarm regularly to ensure that the alarm is operating normally and that the battery is properly connected and has power