Index Card Holder (mountable)
This is a index card (half-cut) holder designed to mount onto a white board. It also has a drop in/clip in "fine point" dry erase holder for up to 4 markers.
Print with something like 5-10% infill and in abs if possible (PLA may be prone to cracking as seen in image; if you're like me and tend to over-tighten EVERYTHING). This only holds index cards that are cut in half.