SPI Molded Parts - Custom molding the future Experience excellence in custom plastic molding with SPI Group, an industry-leader. We offer precision, quality, and innovation, delivering tailored solutions to meet your unique requirements. Discove Custom injection molder since 1952. Freight Securement, Emergency Vehicles, Safety, Agricultural, Musical Instrument Cases, Electronic (Thin-Wall) components, Plumbing/Fluid handling and Hand Tools.