The Multi-Gas Meter is a portable and handheld instrument that is capable to use continuously monitoring four different gas: O, LEL, CO, HS, when detected these gases, all the concentration will displayed on the LCD. The unit also provided user to configure high and low alarms, also STEL/TWA alarm function. The unit has audio and visual alarm once the alarm condition is exceeded.It is capable of detecting 4 kinds of gas: carbon monoxide (CO), hydrogen sulfide (HS), oxygen (O) and combustible gas (LEL)Premium material and selected top quality electronic components ensure excellent sensitivity and accurate measurementPocket-size, light weight and ergonomics design make it convenient to carry and useBuilt in 2500mAh lithium-ion battery after a full charge allows this alarm to work for 8 hours operation, and work about 6 hours with external gas sampling pumpBacklight enables you to see the value clearly even in dark environment2 alarm methods: audio alarm and icons showed on the screenVarious functions meet your demand: gas monitoring, peak value display, low alarm setting mode, high alarm/TWA setting mode, etc.It is suitable to be used in petroleum, chemical industry, metallurgy, refining, etc.Specifications:Brand: SMART SENSORModel: ST8990Material: ABSCarbon Monoxide Range: 0999ppmHydrogen Sulfide Range: 0500ppmOxygen Range: 030%VOLCombustible Gas Range: 0100%LELOperation Current: 220mAShort Circuit Current: 3AOperation Voltage: 3.7VMaximum Open Circuit Voltage: 4.2ABattery: Lithium batteryBattery Capacity: 2500mAhDisplay Type: Segment type LCDOperation Humidity: 15%~95%RHOperation Temperature: 1050Storage Temperature: 040Item Size: 11.45 * 6.44 * 4.45cm / 4.50 * 2.53 * 1.75inItem Weight: 200g / 7ozNotes:Gas monitor only, other accessories are not included.Due to manual measurement, there may be deviation.Due to photograph light or other reasons, the item in picture and material object may have slight difference, please in kind prevail.Please read the manual carefully before you use it.Package included:1 x Multi-Gas Meter1 x Charging Adapter1 x USB Cable1 x English and Chinese User Manual