This is a super simple expandable headphone hanger system. It is intended to be wall mounted, and the model includes a single countersunk hole for a drywall screw. Be sure to print 'Headphone Hanger (top)' as that is the piece that gets screwed into the mounting point. Once you have that piece you can print as many bottom pieces as you like. Note that this will need to be wall mounted as the pieces are too flexible to hold weight without something supporting the back. PLA seems to be plenty strong for four headphones.
Print Settings I Used: Printer: Bambu Lab X1 Carbon Layer height: .2mm Infill: Grid, 15% Filament: PLA