Corner Extension: Make the most of unused space at your corner workstation with this sturdy platform that attaches to the corner of your L-shaped desk, creating additional room for a keyboard above or beneath the table surface Compatible: The 16.8' x 9.8' platform secures to desks up to 1.4' in thickness and fits VIVO under-desk keyboard trays: MOUNT-KB01, MOUNT-KB03B, and MOUNT-KB04C. These compatible trays lower your typing surface for a more comfortable layout