Aluminum works best when molding polymers like thermoplastic polyolefins (TPOs), polyethylene (PEs), and polypropylene (PP). These plastics account for over 70% of the plastics in a typical car.

German rotational mold maker Maus GmbH made a mold using steel and machined aluminum sections to rotomold a portable toilet. Company officials showed the hybrid design at the Rotoplas trade show.