"The MAC722 adds support for two displays side-by-side to carts and floor stands.Note: If you have already ordered a universal cart or stand, you only need to order one interface bracket since these stands come with a universal interface bracket. If you do not ordered a universal cart or stand, you will need two interface brackets (one for each sceeen).- Supports two 39.2-58.8"" (99.6 - 149.4 cm) wide displays (must be same size)"