White. The Abus CO2WM110 is a carbon dioxide detector which reliably warns of increased indoor C02 concentrations, temperature and humidity. A large OLED display with LED colour indicator clearly displays relevant information and it has an integrated acoustic alarm. This detector is powered by micro USB via the AC adaptor and has a built in 3.7 V lithium-ion backup battery. . Power supplied via micro USB cable and AC adaptor (included). Built in battery backup. C02 sensor service life - Max 10 years. OLED display