BMW 3 Series F30, F31, F34, F80 (2011 - 2018) Rear Subframe Rear Mounting Bush (Track/Msport) - PFR5-422BLK PFR5-422BLK is a full replacement bush and is made using our Black 95A durometer material, providing the stiffest link between subframe and chassis, for hard track and motorsport use. For inserts that fit into the OE bush use PFR5-421 for 33316758260 or PFR5-1921 for 33316792510. - NOTE: Price is for CAR KIT, NOT per bush… Powerflex price their bushes individually, but we have combined the quantities to make it simple!