A four gas personal monitor with advanced features including large LCD which can display 4-gas concentrations, current time, and battery indicator simultaneously. Extra loud alarm buzzer, three bright LED lamps and IP67 water and dust proof construction with built in impact resistant protective cover. All controls and features are operated by 2 buttons. Simultaneously and read-time detection of 4 gases LEL, O2 (Oxygen), H2S (Hydrogen Sulfide) and CO (Carbon Monoxide)., Rechargeable Ni-MH battery pack, Continuous operation for up to 20 hours, Data logging standard., STEL (Short Term Exposure Limit) and TWA (Time Weighted Average) readout. Application :Confined space / Refineries and Petrochemical / Utilities / Chemical plants / Hazardous material / Water and wastewater treatment / Fire services