Just a tray I made. Not sure what inspired it. It's obviously quite wide and flat, so at the expense of a little extra material I added a 1mm rim on the bottom in hopes of alleviating the effects of warping that you see in the photo. So use support and a good amount of space between it and the model in X+Y. As modeled, the insert is slightly smaller than the recess it fits into, however I still had to scale it down to fit, which will vary based on your machine.
The author marked this model as their own original creation.