The SD800 is a CO2/Humidity/Temperature Datalogger designed for monitoring and recording environmental conditions. It features a maintenance-free, dual-wavelength NDIR CO2 sensor and a triple LCD that simultaneously displays all three measurements. The device measures CO2 from 0 to 4,000ppm, temperature from 32 to 122°F (0 to 50°C), and relative humidity from 10 to 90%. Data is date/time stamped and stored on an SD card in an Excel-compatible format for easy transfer and analysis. It is ideal for monitoring air quality in schools, office buildings, greenhouses, hospitals, and other locations where high levels of CO2 may be present.