Check the listing for details. HUNTER PCM-300 3 ZONE EXPANSION BLACK MODULE PRO-C CONTROLLERS. Condition: New. Listed at 53.95 USD. HUNTER PCM-300 3 ZONE EXPANSION MODHunter PCM-300 3 Station Black Expansion Module for the Pro-C Indoor and Outdoor Controller Add 3 zones to your existing Pro-C controller This is the new BLACK version of the PCM-300 THIS WILL WORK WITH ALL MODULAR PRO-C CONTROLLERS, OLD or NEW, Black modules CAN be used in a controller that is already running with grey modules installed. If your controller currently works with grey modules, you CAN use black modules along with the grey modules. If you purchase a new Pro-C controller that comes from Hunter with black modules, please note that you can NOT re-use old gray modules inside a new Pro-C controller that comes factory equipped with black modules. New Pro-C controllers will support ONLY BLACK modules.