Designed to measure CO concentration, humidity, and air temperature, AQM-103 Series is suited for indoor air quality diagnosis and HVAC performance verification. CE-compliant device features large LCD that shows measurements as well as date and time with programmable high alarm and audible/visible LED warning light for high CO concentration. With CO measurement range from 0–999 ppm, monitor/data logger offers 1 ppm resolution and accuracy of ±5% of reading or ±10 ppm, whichever is greater.