SCOTT DRAKE These premium bushings are made from synthetic elastomer that provides very similar handling performance and longevity when compared to Polyurethane but without the squeaking. This modern material is firmer than OEM Rubber but has a slightly softer durometer than traditional polyurethane which will improve overall ride quality by eliminating some of the harshness associated with polyurethane. A great compromise that allows you to get both comfort and performance at the same time. Steel Sleeves and correct Washers included. If required the correct 11/16x18 Nuts available under part # 380460-S