Gravitax compatible balls storage

Bought Gravitrax but it lacks a descent balls storage.

This is my first design in Shapr3D for my IPad.

Just print this part twice add the magnets (ø5 mm, 1.5 mm thick)
Make sure you place the magnets for each side with same magnetic pole [N N] [S S] so it will attach in both directions.

I am not related to Gravitrax and this solution just compatible with the supplied metal balls.