This indoor air quality (IAQ) datalogger measures Oxygen, Carbon Dioxide, Carbon Monoxide, Temperature and Humidity. The SD-9901 is capable of recording readings from 3 probes simultaneously and displays measurements on a large backlit LCD. Using a SD card (max 16Gb), a user can select a desired sampling rate and quickly generate an Excel file on a SD card without the use of software. Included: - SD 9901 Reader - CO Probe, CO2 Probe, O2 Probe - Tripod (not pictured) - 4GB SD card - Hard Carrying Case