This is a track you can use to join a modular railway the easy way and It is only 2 magnets holding the track.
Both for 32mm and 45mm gauge tracks.
There is STL files for complete track, track you assemble by your self and complete track for dual extruder printers.
Except 3d-printed parts you need 2 rare(strong) magnets and 2 M4 nuts. the picture are self explaining i think :)