Active Workstation Legs: Designed for DIY tables, this ergonomic standing desk frame gives you the height adjustment you want with customization options (table top must be purchased separately) Compatibility: Recommended Tabletop Sizes - Length of 37' to 77.5', Width of 23' to 43', and a thickness of 3/4' and greater (Actual Frame Length: 36.8' to 57.5', Frame Height: 28.2' to 47.4')