This is a remixed Gridfinity tool holder for 10 hex base metal pin punches (e.g. 9 pc Pin Punch Set (princessauto.com)). The hex dimension is 3/8", but the hole hex is 10.45 mm, which allows approximately 1mm clearance for each punch.

I suggest printing a test piece first to ensure the hex holes provide enough clearance for your tools: I have included a 3mm high test model that should print in about five minutes using the settings below.

I also altered the magnet holes in the base, so that they print a little cleaner without supports.

The remix was done on Tinkercad, and can be seen / copied / remixed using this link: https://www.tinkercad.com/things/cUfzSaCyp9y?sharecode=YmIOCHaTNztS8WKd5AIX2nrJtvQdbfu-PRJcXNrvC9U

I printed this using PLA on an Ender 3v2 with an 8mm nozzle, at 200 degrees C, with a bed at 50 degrees. Layer height was 0.32mm (draft quality), 20% cubic infill, no supports, with print speed at 50mm per second.