A replacement strap for Crocs, UK men's size 11/EU size 46, it will probably work for close sizes like 9-13.
I printed in TPU-95.

I suggest you face the print bed side towards the foot when fitting the strap to the shoe, so the smoothest surface is touching the foot to prevent blisters/chaffing. Also this allows the less densely printed top skin to stretch to accommodate the curvature of the strap.

It takes quite some force to push the strap button through the strap hole, I managed with just my fingers and a lot of force. You may want to use a tool like circlip or needle nosed pliers to assist with stretching the strap hole when attaching the strap if your fingers are not strong. 

Warming up the end of the strap in a cup of freshly boiled water for 2 minutes makes putting the strap on much easier.