kettlebell 3d model

Create a 3D-printable, watertight competition-style kettlebell shell model. The model must feature a uniform wall thickness of 6mm throughout, making the entire interior completely hollow from the bottom base all the way up through the handle. The main lower body must feature prominent, deeply recessed, smooth oval-shaped flat ergonomic forearm scallops on its lateral faces to distribute weight comfortably against the forearms during use, matching the aesthetic of premium fitness equipment. The top handle loop must be a hollow tube continuous with the main hollow body cavity. The absolute bottom base of the kettlebell must be completely flat and feature a circular 3.5-inch diameter bottom-fill port opening with deep structural screw threads. Generate a separate, matching 3.5-inch threaded circular sealing cap that screws perfectly into this bottom fill-port. All exterior surfaces must be perfectly smooth, clean, and optimized for 3D printing.