Gravitrax Marble Ballbox

This is a remix of https://www.thingiverse.com/thing:5404352

I took his idea and put together my "own" Box with slightly changes:
1. The box is a bit larger (2mm thick walls)
2. you need 2x2 magnets with 5mm diameter and 2mm in height
3. the marbleholes are 13mm in diameter (the marbles are 12.7mm)

It works like the one I remixed mine from, so print it twice.
I put the magnets in opposite directions in each of the two parts. So one side of one part north is facing up, and on the other side south is facing up. Like this you have identical top and bottom parts and can mix them between more then one box.