Genuine BMW M Performance Limited Slip Differential. Fit F20, F21, F22, F23. It is your responsibility to make sure it fits your vehicle. If goods are faulty, we will replace the item free of charge, if notified within seven days of the end of the sale. Electric items are not returnable if they have been used. We are a main BMW / MINI retail centre so can meet all enquiries. We also have large workshops if you need something fitted.