I was annoyed, that the Tray in our Shower was always full, so i made an Extender.
it is not the most stable Structure but it holds three half empty bottles easily. Assemle in your Shower by sliding the tray holders in between the rods of the existing holder, then use glue if u want.
3 walls, 50% infill
i used ABS but PETG and even PLA (if u don't shower with Lava lol) should be fine.
The author marked this model as their own original creation.