This Polyurethane rear track bar bushing kit from prothane fits 07-16 Jeep Wrangler JK/JKU. The Rugged Ridge Polyurethane rear track bar bushing kit, in red, comes with four track bushings and metal sleeves. There has been an ongoing debate about rubber vs. Polyurethane as to what is better, it truly depends on how you are using your Jeep. In most cases Polyurethane outperforms its rubber counterparts in replacement of bushings and mounts. The products will last longer standing up to road debris, chemicals, oils, compression, and load. They will perform better by removing additional sloppiness in suspension performance due to worn, damaged, or missing bushings. It is however, a little stiffer than rubber.