The Whiteline 05+ BMW 1 Series / 3/05-10/11 BMW 3 Series Rear Crossmember-Front & Rear Mount Bushing is a suspension component designed to improve the performance and handling of BMW 1 and 3 series vehicles. The bushing is made from polyurethane and is designed to reduce noise, vibration, and harshness (NVH) while providing improved handling and stability. The bushing is designed to replace the original rubber bushings, which can become worn and reduce performance. The bushing also helps to maintain alignment and prevents excessive movement of the rear crossmember, which can lead to premature wear of other suspension components.