Claim: Powertrack Hobbyists (persons who pursue a particular hobby) have created shells of four car models.
Evidence: Keen hobbyists have produced alternate shells for existing chassis examples are listed below, the makers of such shells are as yet unknown. Hobbyists may be identified under three sub-categories: casual leisure which is intrinsically rewarding, short-lived, pleasurable activity requiring little or no preparation, serious leisure which is the systematic pursuit of an amateur, hobbyist, or volunteer that is substantial, rewarding and results in a sense of accomplishment, and finally project-based leisure which is a short-term often a one-off project that is rewarding.