21700 case magnet closure

Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:4064619.

I liked the 18650 case by behufe but needed a 21700 case so i just used a little math and used tinkercad to expand the case size. I used 5x3mm magnets

https://www.thingiverse.com/thing:3787274