This is a two piece print that can be done with no supports. The bracket is 22.5mm, which fit perfect on the jogging stroller used for testing. the cupholder slides onto the bracket easily but very snug. When folding stroller the cupholder can be removed and the bracket can be left on the stroller. There is a hole in the bracket for option to drill a screw for extra strength. Tested using a full 30oz Stanley cup and had no problems running and turning the Stoller or bumping and hitting the cupholder while being used. 3mf was downloaded from prusa slicer and not bambu so this file specifically does have supports.