Feature:1. Premium material and selected top quality electronic components ensure excellent sensitivity and accurate measurement.2. Pocket-size, light weight and ergonomics design make it convenient to carry and use.3. Built 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 pump.4. Backlight enables you to see the value clearly even in dark environment.5. 2 alarm methods: audio alarm and icons showed on the screen.6. Various functions meet your demand: gas monitoring, peak value display, low alarm setting mode, high alarm/TWA setting mode, etc.7. It is suitable to be used in petroleum, chemical industry, metallurgy, refining, etc.Specification:Introduction:The Multi-Gas Meter is a portable and handheld instrument that is capable to use continuously monitoring four different gas: O₂, LEL, CO, H₂S, 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.Features:It is capable of detecting 4 kinds of gas: carbon monoxide(CO), hydrogen sulfide(H₂S), oxygen(O₂) and combustible gas(LEL).Premium material and selected top quality electronic components ensure excellent sensitivity and accurate measurement.Pocket-size, light weight and ergonomics design make it convenient to carry and use.Built 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 pump.Backlight enables you to see the value clearly even in dark environment.2 alarm methods: audio alarm and icons showed on the screen.Various 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: ST8990Color: YellowMaterial: ABSCarbon Monoxide Range: 0～999ppmHydrogen Sulfide Range: 0～500ppmOxygen Range: 0～30%VOLCombustible Gas Range: 0～100%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: 10℃～50℃Storage Temperature: 0～40℃Item Size: 11.45 * 6.44 * 4.45cm / 4.50 * 2.53 * 1.75inItem Weight: 200g / 7ozPackage Size: 20 * 11 * 7cm / 7.87 * 4.33 * 2.75inPackage Weight: 475g / 16.8ozNotes:-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.Packing List:1* Multi-Gas Meter1* Manual1* USB CablePackage List:1* Multi-Gas Meter1* Manual1* USB Cable