Made in USA. Machined from billet aluminum, this Pure Stealth GM Throttle Body & Tune Port Fitting Kit includes one 14MM-1.5 x -6AN metric o-ring adapter fitting and one 16MM-1.5 x -6AN metric o-ring adapter fitting complete with Viton o-ring seals. Fitting is coated with our proprietary Pure Stealth black ceramic coating. The coating is extremely durable but it can be scratched. Care should be taken during installation process to prevent damaging the coating.