. . . . "Biocompatible materials include, but are not limited to, plastic (including acrylics, polystyrene and copolymers of styrene and other materials, polypropylene, polyethylene, polybutylene, polyimide, polycarbonate, polyurethanes, Teflon???, and derivatives thereof, etc.) Other configurations include combinations of plastic and printed circuit board (PCB; defined below)." . .