The car batteries you will find on this page include – but are not limited to - the following sizes: 008, 014, 069, 037, 077, 038, 048, 049, 421, 111, 421, 082, 062, 069, 114, 086, 027, 096, and 020. The three-digit numbers listed above relate to the size of the battery you need. Yet just because your car’s battery bay will accommodate a power source in terms of size, this doesn’t mean that it is the right one for you. When choosing a battery, the main specifications to note are amp-hours (Ah) and cold cranking amps (CCA). Ah refers to the battery’s lifespan, while CCA refers to the battery’s ability to start your car in cold weather. Another factor to consider is whether or not you want a maintenance-free battery. Those that need maintenance require you to monitor electrolyte levels. Maintenance-free batteries do cost more, but give you the benefit of stress-free operation.