The Wilwood AERO4 Rear Kit 14.00 2007-2011 BMW E90 Series w/Lines is a performance brake upgrade designed specifically for the BMW E90 series. This kit includes two Wilwood AERO4 calipers, two Wilwood 12.19” rotors, stainless steel brake lines, and all necessary mounting hardware. The Wilwood AERO4 calipers are lightweight and feature a four-piston design for superior braking performance. The 12.19” rotors provide increased heat capacity, improved pad life, and enhanced braking performance. This kit is an ideal choice for those looking to upgrade their brakes for improved performance and style.