.They use a unique Polyurethane blend that ensures long life and consistent performance. Like the rest of Daystars extensive Polyurethane kits, Daystar Spring and Shackle Bushings are an excellent upgrade over stock rubber bushings. Features:86-92 Jeep MJ Comanche RearReduces Body Roll And ShiftReduces Stress On Steering ComponentsImproves Handling CharacteristicsVehicle Fluid And Road Grime Resistant Whether it's a vehicle restoration or an upgrade over rubber, Daystar spring and shackle bushings make a difference you can feel.