I need a 3-D model I can send straight to my printer that will let me hang a helmet from the two metal posts of a car head-rest. The design must be optimised for plastic 3d printing, so wall thicknesses, overhangs, and any built-in supports should reflect that. The hanger has to work with any common helmet style—motorcycle, bicycle, construction, or anything similar—so add a simple, reliable retention feature (for example a lip, cradle, or snap-fit clip) that prevents the helmet from sliding off in normal driving conditions. Standard head-rest post spacing varies from roughly 110–165 mm; if you can build in slight adjustability or an easy print-time scale option, even better. Deliverables • Printable file set (STL + original CAD such as STEP or Fusion 360) • Brief print recommendations: orientation, layer height, infill, and any insert hardware if you choose to use it Once I confirm fit on my own head-rest and the helmet sits securely without rattling, the job is done. I am interested in making future models with the addition of electronics.