If you drive your BMW through the winter and are running a coilover setup, you need these. Here in the New England area, we use salt to clear our roads of snow. Unfortunately, corrosion seizes coilovers almost instantly, making it impossible to adjust your previously fully adjustable coilovers. Recognizing the importance of keeping your vehicle adjustable, we made our own coilover covers to keep salt, road debris and grime away from your coilovers and keep your coilover lock rings spinning freely.