Records data on an SD card in Excel format for easy transfer to a PC for analysis. Features: Checks for Carbon Dioxide (CO2) concentrations Maintenance free dual wavelength NDIR (non-dispersive infrared) CO2 sensor Triple LCD simultaneously displays CO2, Temperature and Relative Humidity Measurement ranges: CO2 - 0 to 4,000ppm; Temperature - 32 to 122°F (0 to 50°C); Humidity - 10 to 90%RH Datalogger stores readings on an SD card in Excel® format for easy transfer to a PC Extech SD800 CO2 / Humidity / Temperature Datalogger Monitor air quality in schools, office buildings, greenhouses, hospitals and anywhere that high levels of carbon dioxide are generated. CO2/Humidity/Temperature Datalogger checks for Carbon Dioxide concentrations and records data on a 2 GB SD card in Microsoft Excel format for easy transfer to a PC for analysis. A triple LCD simultaneously displays all three parameters, and a selectable data sampling rate of 5, 10, 30, 60, 120, 300, and 600 seconds. Each stored reading includes a date and time stamp. Measurement Ranges: 0 to 4,000ppm CO2; 10 to 95 percent RH; -58 to 2372 degrees F (-100 to 1300 degrees C) Temperature. Spec Sheets Extech SD800 Data Sheet Specifications Extech SD800 Specifications CO2: 0 to 4,000ppm Accuracy: ±40ppm (1000ppm) Resolution: 1ppm Temperature: 32 to 122°F (0 to 50°C) Accuracy: ±1.8°F/0.8°C Resolution: 0.1°F/°C Humidity: 10 to 90% Accuracy: ±4%RH Resolution: 0.1% Datalogging: 2,000K data using 2G SD memory card Dimensions: 5.2 x 3.1 x 1.3" (132 x 80 x 32mm) Weight: 9.9oz (282g)