Features:Supper large LCD simultaneously display and log Carbon Dioxide Level, Temperature,relativehumidity, Calendar (Y/M/D) and Time (Clock)12700 data logging memoryWarning CARBON DIOXIDE LEVELStable NDIR sensor for Carbon Dioxide concentrationNDIR (Non-Dispersive Infrared) WAVEGUIDE TECHNOLOGY WITH ABC (Automatic back-ground Calibration)High and low threshold settingBack-light function, Recall Max and Min reading and Long time drift compensation.Specification:Large LCE display: 3.5 inch (8.9 cm) LCD display with backlightLogger mode: keypad statistics/stop, now, plan, real time and flipCarbon dioxide range: 0~9999 (out of range)Accuracy:50ppm5%rdg0~5000Response time: 10 secondsTemperature range: -10.0~70.0(14~158)Resolution: 0.1/Accuracy:0.6/0.90~50/ 32~122,other1.2Humidity range: 0.1~ 99.9%Resolution: 0.1%Accuracy:3%10~90%Record memory: 40,000Working conditions: 0 ~ 50, 0 ~ 95% RHStorage conditions: - 20 ~ 60, 0 ~ 99% RHSensor life: normally 15 yearsStorage temperature: -40~70(-40~158)Power supply: 1A output 9V AC adapter or 2 pairs of 1.5v AA batteries (not included)Color: whiteMaterial: ABS+TPUSize: 14*10*4cm/5.5*3.9*1.6inWeight: Approx.794g/28ozPackage list:1 x tool box1 x carbon dioxide detector(batteries not included)1 x USB data cable1 x CD1 x English user manual1 x cardboard box