The RTR-576 CO2 Wireless Temperature Humidity Data Logger measures and records Carbon Dioxide (CO2) Concentrations, Temperature and Humidity. This wireless data logger features Battery-Powered, 1 second to 1 Hour Sampling Rate and Stores 8,000 Samples if Wireless Communications Are Not Available. TandD RTR-576 Measures and Records CO2, Humidity and Temperature Readings CO2 Measurement Range: 0 to 9,999ppm Humidity Measurement Range: 10% to 95% RH Temperature Measurement Range: 0°C to 55°C Stores up to 8,000 Data Samples Between Wireless Transmissions to Base Collector or Repeater Sampling Rate: 1 Second to 1 Hour 150 Meters Line of Sight Transmission Between Devices (Logger to Base Collector or Repeaters) WebStorage Service available Additional Base Station required for communication