This is a shower shelf that attaches to the bar that holds the shower head. It is large enough to hold a couple shampoo and conditioner bottles and a shower beer. The cutouts on the front and bottom are voronoi pattern. This is also a little beefier than the original in order to hold more weight. I also made the 2 halves flush instead of having a fillet in between that made a gap. 

Edit: Added a file for an 18mm Bar Diameter.