Whiteboard marker holder

This is a holder for whiteboard or chalkboard markers. You need to print two pieces and have to screw them on a thin plywood plate or similar. The maximum pen diameter is 18mm.

I redesigned this thing (https://www.thingiverse.com/thing:3062109) from Quad_out because I want to use the holder on a metal door with magnets and the original hooks to hang the holder were not necessary for my case of usage.