Measuring Range: 0-2000 PPM CO2 Accuracy: +/-2%PPM Precision:10 PPM Recording Capacity:7000 groups Recording Interval:2 seconds-24 hours Connecting Port: RS-232 or USB Source of power: AC220V / DC5V Software: Chinese & English Edition Can be used in recording co2 in the air or other condition.Widly used in area as agricultural research, pharmaceutical and chemical industry, transport, environment protection,