BMW 3 Series E90, E91, E92 & E93 (2005-2013) Rear Subframe Rear Mounting Insert - PFR5-421 PFR5-421 is an Insert to be used with the OE rubber bush. For a full replacement bush use PFR5-422 - NOTE: Price is for CAR KIT, NOT per bush… Powerflex price their bushes individually, but we have combined the quantities to make it simple!