The CO50 is a desktop CO Monitor which measures and displays carbon monoxide concentration, air temperature and humidity simultaneously. The CO50 features visibly bright LED lights which indicate active monitoring (green) or a surpassed CO alarm threshold (red). The meter also features an extra loud audible beeper alarm, electrochemical CO sensor, record, recall Max reading for CO concentration and CO calibration function in fresh air. Product is complete with Universal AC adapter with multiple plug types (US, EU, UK, AUS) and a user's manual.