Carbon Monoxide alarm (carbon monoxide, CO detector) 1.EN50291 Carbon Monoxide alarm with EN50291 (carbon monoxide, CO detector)Main Features:1.Non-radioactive technology for environmental friendly2.CO ... missing warning indicator8.Hush/Test button9.Auto-reset when CO clears10.CE, TUV approved, comply with EN50291, ... TypeElectrochemicalAmbient Humidity15% to 90% Relative Humidity Carbon Monoxide alarm