INDOOR AIR QUALITY MONITOR - Detect rise and decrease in carbon dioxide level, perfect for anyone wanting to monitor air quality! Elevated CO2 can cause symptoms like headaches, drowsiness, allergies and difficulty concentrating, to keep an eye on air quality at home or work!
USB POWERED OPTION & BATTERY BACKUP & ADJUSTABLE BACKLIGHT It is plugged in which allow the multi brightness display to stay on all the time, if you prefer. Either set it on tabletops, or mount it on the wall. 3 x AAA Battery (not included) for Backup & outdoor manual calibration.
calibration process: Place the device in a standard calibration environment of 400PPM, Press and hold the ALERT button, and power on the device or install the battery, The device will sound "Bi-BI" and the screen will display the "CAL" character and keep blinking, After three minutes of calibration, the "PASS" character will be displayed. Power off and power on the device.