They're made out of delrin usually so they are basically solid plastic=) The wear characteristics of delrin are good so you won't have to worry about it wearing out any time soon. They use delrin to make solid subframe bushings and other suspension bushings too. __________________ 95 318ti & 96 318ti Quote: Originally Posted by eurohb  Im Jelly.. enough said. |  Follow me on instagram: earlmeyeriii |