Holder for the 11-piece Wiha imperial T-handle hex wrench / allen key set PN 33494. That's a great set, providing all sizes from 5/64" through 3/8".

The rack is specifically designed for the Wiha set in regard to handle thickness and the 11 sizes, but it will likely hold a lot of other imperial sets without any trouble.

This design supports both magnetic hold-down as well as legs for use on non-ferrous surfaces. The legs snap into the magnet holes so if you want to switch from magnetic to legs, you need to remove the magnets. If you want to mount it on a wall, you'll need to drill some holes to screw the legs into the holder base, and to attach the legs to the wall. 3M Command strips might be strong enough to attach the legs to a vertical surface.

The magnets and plastic self-tapping screws are from McMaster: Magnet - https://www.mcmaster.com/5862K14/ Screws - https://www.mcmaster.com/95893A218/

I'd like to acknowledge all the other people who have published T-handle hex key racks. This is a ground-up design and not a remix of any one specific Thing, but it owes various features to several.

The CAD file is here in OnShape: https://cad.onshape.com/documents/8f10bfd6ca3c32220d607198/w/36edc721ddddd9a498f7f42d/e/396148b4803f52dd8bfca454

It's parameterized so that you can adjust the height, width, leg dimensions, etc. as desired.

This part is pretty long; it will fit diagonally on a Prusa MK3S but not on smaller print beds. I printed mine at 100% infill to put more weight into it so it will stand up better with short legs.