Marble Run Support Piece

Modeled to be compatible with the Joyin(?) marble run set. The set did not come with nearly enough of these. Pretty sure that this also compatible with the Marble Genius and NatGeo marble run kits because they look like they're all about the same. If not, it should only need minimal adjustments.

My original design was a little to tight of a fit, so I added the slit in the top to add some give and it works pretty well now.