The Genuine BMW Coil Spring Shim - 31336860788 is a small, metal shim designed to be placed between the coil spring and the strut assembly in a BMW vehicle. It is used to adjust the height and tension of the coil spring, allowing for a more precise suspension setup. This shim is an authentic BMW part and is made to the highest quality standards for optimal performance and durability. It is compatible with a variety of BMW models and is an essential component in maintaining a smooth and stable ride.