ARIKON CO Carbon Monoxide Alarm Detector with Clock [Battery Included], LCD Display, Talking Alarm, Best Used At Home and Travel, Portable CO Detector 1. Market leading electrochemical sensor and auto detect sensor failure - offering great peace of mind and protecting you and your family from the dangers of CO 2. LCD digital display with 24 hours clock system and carbon monoxide concentration (PPM), battery capacity 3. Low power consumption, long standby time,so stress free protection 4. Very convenient to install at home, kitchen or car with wall mount (screws included) or portable (stand included) 5. Pass the CE & ROHS Certification and meets UL2034 standards