parts. Had no idea Z1 and others made this cheap stamped crap and not tell you about it. The gasket that comes in the kit is over a 1/16 of an inch thick so I don't believe you would have to overtighten the screws to get it to seal. Than being said crap is crap, no way arouund it. Wish these businesses were more explicit about their products. I'm on this forum all the time and had never encoountered this discussion. You can be sure I would have never gone with substandard materials knowingly.