Holds my HDMI switcher onto my desk riser. the desk is 20mm. I taped and glued the rack and my mouse switcher button onto it. 

HDMI:https://www.amazon.com/gp/product/B07VPD3BXC/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

USB:https://www.amazon.com/gp/product/B09QKR3YY9/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1