Description BX616 portable four-gas detector can make continuous detection to combustible and toxic gases to protect the disasters caused by the O2 deficiency, toxic gas poisoning and combustible gas. Once the gas concentration is abnormal, it sends out an alarm. It is suitable for steel plant, petrochemical plant, petroleum industry, shipbuilding yard, sewage treatment plant, mine, power supply engineering, confined space, etc. Key Features 100, 000 detected records including peak value Calibration point adjustable Two alarm level for each sensor channel STEL& TWA alarm for toxic gases Visual/audible/vibrating alarm Self protection against high concentration combustible gas Low battery alert Confidence beep Data uploading Password management Self-test when power on Self-diagnostic and self correction function