I've designed simple, but elegant wall-mounted holder specifically for the basic Wet Brush.

This design is great for renters as it is built around / sized for using 2 small Command Strips. It has a trick up its sleeve though, allowing for the pull tabs to be hidden from sight (except when viewed from below). They can easily be snipped, tucked away, then unfolded with tweezers when it's time to remove it from the wall (see photos below).

In case you want the option to use screws for installation, I've included 2 [untested] alternate versions. One is just meant for screws, while the other is meant to be more versatile (hybrid).

I printed mine (as shown) in Bambu PLA Basic Purple at 0.16mm layer height on my Bambu Lab P1S.

Enjoy, and happy printing/brushing!

Note:
I'm working on an additional cover to go with it so that you can keep the dust out of your brush as well.

No supports are necessary. It can be printed upside-up or upside-down, depending on how you want it to look:

The cool part demonstrated: