When your car battery dies, it is not a simple case of buying any model to replace it. Your car requires a specific type of battery with specific dimensions – you will find details of these in your owner’s manual. If you are not sure, it is a good idea to consult a specialist so you can be sure that you are buying the right one. 643 car batteries are often fitted to heavier duty cars like 4x4s and people carriers, so it is vitally important that you choose one that is going to make your car run at its optimum power.