The GHK12X2CH is the most recent version of the GHK12X2. This model    is equipped with all of the great features of the original GHK12X2 combined  with the features of the GHK12X2C and H. The programmable temperature    setting in DIF, DAY & NITE stages; 2 HEAT, 4 COOL steps with    automatic and manual setting; TIMER and ALARM outputs; 1 or 2 zones;    VENT stage for dehumidification; STATISTICS (min, max, and 7 days of    temperature averages) come with the curtain/vent control and set point heat    and additional temperature sensor in this GHK12X2CH controller. The    GHK12X2C is compatible with CIS software to connect multiple    controllers to a personal computer for programming and monitoring.