Fit is perfect, price is right, delivery was quick. Plastic Material. Just put in place of existing gasket, thin enough, appx 3/16", where I haven't used longer bolts. No leaks air or water, tighten nuts / bolts, run the vehicle and tighten again the next day - after that the nuts and bolts were set. Provides a very noticeable temp difference between the head and intake manifold.