FACT: Teenagers are unable to hang towels up in the bathroom. SOLUTION: 3D print yourself this handy simple towel clip, insert a 20mm diameter ball, the clip has enough 'give' to allow the ball to push in from the side - but it wont fall out. (the ball can be bought or 3D printed as well). Slip the towel up behind the floating ball - ball drops down locking the towel firmly in place. A quick pull on the towel to release it. Fix to the bathroom door or wall and never again deal with a towel covered bathroom floor! Print at 0.2mm, high% infill - no support or raft needed for clip. Ball may require some support if you wish. Print ball at 100% infill to give it some 'weight' or purchase a 20mm steel ball or marble from any good toy/hardware store. Scale the Towel clip up or down for other sizes of ball insert. Enjoy!