OEM Custom Power Bank Shells for Precision Electronics Manufacturing WIN-WIN Electrical manufactures OEM custom power bank shells using precision injection molding and custom mold development. Our plastic enclosures can be tailored to your product dimensions, internal components, charging ports, buttons, materials, colors, and surface finishes. Designed for B2B electronics projects, our custom power bank housings support product development, OEM production, and scalable manufacturing for portable chargers and related electronic devices.