I was not happy with the spring loaded display mount that came with my Onefinity Journeyman, so I made my own that mounts on top of the table. No supports are needed and it bolts directly to the spring loaded frame supplied by Onefinity. The only extra you need is an M5 bolt to use for the pivot on the mounting arm. Length is not super important as long as it is longer than the arm. The longer it is, the stronger the pivot.