This is a replacement support part for a folding chair. The model is a little tight for the chair tube but you can adjust as needed as I also attached the original model done in Autodesk Inventor. I printed on Afinia Up Machine.
I printed in ABS and tested two different orientations (See picture). The upside down print without support worked the best for me.
I reverse engineered a part from another chair that still had the part in it. Used Autodesk Inventor.