SD800 monitors air quality in schools, business buildings, greenhouses, hospitals, and anywhere substantial volumes of carbon dioxide are produced. Data sample rate can be set to 5, 10, 30, 60, 120, 300, or 600 seconds, or it can be left automatic. Maintenance-free dual wavelength NDIR (non-dispersive infrared) CO2 sensor. CO2, temperature, and relative humidity are all displayed on a triple LCD screen at the same time. Includes six AAA batteries, a 2GB SD memory card, a universal AC adapter, and a mounting bracket.