... *=1&*entries*=0Xi'an Hua Fan Instrument Co.,Ltd is one of the leading 12 portable ... to buy or wholesale gas alarming detectors, CO detector, carbon monoxide detectors made in China from ... separately)Destination gas: oxygen (O2), gas (EX), poisonous and harmful gases (CO, H2S, NH3, CL2, etc.)Response time ... : ≤30s(O2);≤40s(CO);≤20s(EX);Time display: the machine is year, month, ...