A simple suspension bracket for combination keys. This fits into the 6mm to 13mm half of the set.
Holds 2 spanners.
There's also a thing for the 14-19mm half of this set.Paint the end or make a two-color print.
Make it nice and strong, ideally ABS or PET-G with a high fill and wall count.
Holes on the back fit a standard Bott Perfoboard. Screw in the back or fix in the holes. There is nothing to pinpoint, so it can also be installed in a shade frame or wall.