We are offering tv accessories: m-series dual side-by-sidel display accessory. mac722 m-series dual side-by-sidel display accessory 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).