Features: Durable material - This product is made of high-quality material, durable, long service time, firm and stable in use. carbon monoxide detector alarm:suitable for all fields: houses, shops, hotels, restaurants, office buildings, schools, banks, libraries, computer rooms and warehouses, etc. Alarm Standard&Liquid crystal display - the alert time depend the level of carbon monoxide concentration,And the display screen of the carbon monoxide alarm can accurately measure the concentration of carbon monoxide and its concentration data . When the concentration reaches a certain level, carbon monoxide smoke The detector will notify you immediately when it detects it, minimizing false alarms Combination alarm - Battery-powered combination alarm that offers protection from the dual dangers of smoke and carbon monoxide in a single unit for added convenience - The voice alarm feature audibly announces which Danger has been detected to protect your family's life and property safety from CO detector.(Not included battery) Quick & Easy Installation - It can be installed independently, without wires, just three batteries. It can be placed or fixed where you want. Carbon monoxide is lighter than air, so it is recommended to install it the ceiling Installation: 1. Usually the detector should be installed in the bedroom, living area, car and other places where people stay for a long time. It is recommended to install in the bedroom, corridor, basement, car and living area. 2. Since the gas concentration and smoke concentration of carbon monoxide are lighter than air, the detector should be installed at 2-1 meters below the ceiling. 3. When the detector is installed, it is not easy to be too close to the furnace to prevent the detector from being baked by the flame; nor can it be installed in the exhaust fan, the door and window and the bathroom where the water vapor flow is large; nor can it be installed in a place with large smoke. In order to prevent the oil smoke from clogging the air inlet of the detector, the entrance is not smooth, thus affecting the sensitivity of the detector. Specificaiton: Color: White Size: 10*10*4CM Material: ABS Plastic Alarm Current: <70mA Power supply: 3 AA batteries(Not included battery) Working range; humidity 0C~50C