This part replaces a Zome ball where you need to have two blue lines intersecting, lying in the red plane, at an angle of 72 degrees. Its purpose is aesthetic, when you don't want to use a ball to make the junction. This might happen if you're trying to represent a mathematical object wherein balls should represent vertices, not false vertices arising from edge intersections.
Six copies are modeled as a single print, with small sprues connecting the individual bobs. They can be twisted apart, then cleaned up with a sharp knife or nail clippers.