Combination Smoke and Carbon Monoxide Detector Alarm with LCD Display and Voice Warning Battery-Operated Auto-Check Smoke CO Dual Sensor Complies with UL 217 and UL 2034 Standards

chzghe Combination Smoke and Carbon Monoxide Detector Give you the most secure protection. Features: It has electrochemical carbon monoxide sensing technology and an ionization sensor for smoke detection. The LCD display shows the concentration of smoke or carbon monoxide in PPM (parts per million), and the standard 85 decibel alarm sounds a clear and loud warning. Simple and easy to use, use batteries to install, it can be safely protected even when the power is cut; the built-in screws and Anchor Plugs make the installation easy. After rigorous testing, it meets UL217 and UL2043 standards. Packing List:   1 × Alarm Unit 3 Sets × Screws 3 Sets × Anchor Plugs 1 × User Manual (The required 3 2A batteries are not included, please prepare in advance.) Technical parameters: Battery supply: DC 3*1.5V AA Sensor: Electrochemical Carbon Monoxide Sensor and Infrared Photoelectric Sensor Working temperature: 0-50°C Carbon monoxide gas detection concentration: 000~999 PPM Smoke sensitivity : 0.1%db/m-9.9db/m Battery display: low battery alarm Cautions:   This product should not be installed in the following locations: A). Places where smoke is normally trapped B). Locations with a relative humidity greater than 95% C). Places with large dust, water mist, and oil mist pollution D). Locations with high wind speed (greater than 5 m/s)