... light weight, rugged ABS+PC case 2. Changeable different gas sensors for this equipment. 3. Welcome OEM IntroductionWe, ... underground Coal Mine, petrochemical, metallurgical, chemical, municipal gas, and other places at the scene detection; Technical specification ... Alarm sound intensity≥75dBAlarm light≥20M visibleAlarm pointcan be set in full proceedAlarm waySound, lightContinuous working time>3 ...