This is a remix of a Fedora that has been molded to fit very nicely on the head of the MatMireMakes Platypus model: 3D Printable Platypus, Articulated fidget, Print-In-Place, Cute Animal by MatMire Makes (myminifactory.com)

The 100% scale model of this fedora fits great on the 100% scale model of the platypus, and it scales down 1:1. I have not tested it below 50%, or above 100% so do so at your own risk.