This was originally designed for a 62 mm mirror I got from a friend who found them at a local surplus store. I put a lip on it to protect and retain the mirror and 4 8 mm magnets on the back so I could put it on a mill or drill press when trying to center round stock with and indicator. Then a lady friend told me mirrors have other uses too, who'd a thunk it? You can scale or edit to your hearts desire but I do suggest you print in TPU for it's impact resistance and durability, plus the grip is better. The mirror will fit just push down on a table or scale to fit, You might want to use an adhesive to hold the magnets.

Magnets
https://www.amazon.com/gp/product/B01MZ6EJE2/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

Happy Printing