The Best Rite Great Divide 8 ft. High Mobile Room Divider Add-On makes setting up partitions and temporary enclosures is no longer a time consuming affair. This set is designed to join starter sets. When joined with starter sets, this add-on set attempts to create maximum wall length. Its a great support to the modular wall system that allows you to customize wall length. While starter sets include three wall panels and two end panels, these add-on panel set includes two wall panels.