Evolution Carbon Dioxide Controller Full Kit:Click on graphic for larger imageThe Evolution CO2 Controller monitors CO2 Levels within the grow room and constantly adjusts the amount of CO2 to maintain ideal conditions for optimal plant growth. The Evolution CO2 Controller is also compatible with the Evolution Digital Fan Speed Controller The Evolution controller utilizes the latest microprocessor and infra-red technology to monitor & control the levels of carbon dioxide in your growing area.The controller can operate with the Evolution Solid State NDIR CO2 sensor, this controller can also be used with either bottled CO2 gas or with a propane or natural gas burning CO2 generator, in addition to this the Evolution controller can be interfaced to most external thermostat / hygrostats for improved environmental control