This is an idea i got when i needed to Make a three fly Silver Slippery Sam Coin Shell Magnetic in order to dump the shell at the end of my three fly coin routine that i do, onto a magnetic left hand back pocket holdout.
Here is the link to the steel discs that i bought on amazon.
https://www.amazon.com/Mount-Metal-Pl...


https://www.amazon.com/gp/product/B07...