Roco Z21 shelf for 10 inch server rack

I'm using the server rack from NatalieT for all the electronics on my model railroad and needed some specials. This is just a simple remix of the blank shelf to hold a Roco / Fleishmann Z21 firmly in place. It also fits some of the stuff they provide in the same box like the boosters. I made two versions of it. The devices don't get very hot, so the blank shelf is all you need. But if you for some reasons are worried about cooling I made another version to let some air in from below. Original model and rack here: https://www.printables.com/model/1090551-modular-10-inch-server-rack-reworked