Hello, I have been constantly looking for a riser for my mac keyboard and all the ones I found had a set height. I decided to make my own fully adjustable keyboard riser. They way it works is it attaches to both sides of the keyboard and a gear on each turned by a knob lowers a half circle which rises the keyboard as the knob is turned. the keyboard can stay at any spot within the max and minimum height threshold. It is simple to print, but supports are necessary for the piece that attaches directly to the keyboard, but not the gears. I printed this at .3mm layer height with 20% infill and it is strong and looks fantastic. Please check out the linked video below to see it working!  Enjoy! Video of Riser in Action