We have combined digital temperature & humidity controls together in one flexible unit called the EVC-2 / Environmental Controller. It has two additional features which activate a Night Device and a CO2 device. The EVC-2 provides the perfect combination of features The EVC-2 controls your Temperature & Humidity with DIGITAL accuracy. * Photocell allows day / night temperature & humidity settings and also provides daytime CO2 operation. * Remote combination temperature & humidity probe allows the probe to be placed near slant canopy. * Record & recall minimum and maximum temperature & humidity levels. * Two temperature modes, Heating & Cooling. * Separate humidity control to add or remove humidity. * Adjustable temperature dead band.