We frequently get tech questions from readers about what's the best Optima battery for their application. Optima has tech bulletins, tips, and more on their website where you can find answers to many of the questions. However, answering the "right one for me" question is fairly simple. Optima offers three main battery types, all denoted by colored tops--RedTop, YellowTop, and BlueTop. The BlueTop is designed for marine use, so we can rule that one out for Mustangs. The RedTop is a cranking or starting battery, so it should be considered if your primary concern is starting the car, no matter the temperature or starting demands. The YellowTop has cranking power similar to the RedTop, but also features deep cycling capability, which means it can support demanding electrical loads like big audio systems, high key-off electrical loads, and so forth. The YellowTop can "bounce back" from being deeply discharged without damage, unlike conventional batteries.