Good quality black metal bushing. But as some other reviewers have pointed out, the hole is a little less than 2-1/2 inches. This seems to be the problem that plagues these types of products as I assume they are all made in metric/mm and not inches. To avoid a loose fit I chose a 2-3/8" hole saw which is too small but I slowly widened the hole with a file until tight. If available then 2-7/16". A hole saw is perfect for this product.