The XP Series was designed and manufactured for use as a secondary/supplemental power source. They are designed for high capacity installations, so if you need a battery to add some capacity for your system then this is the answer. The XP Series is not designed to be used in under the hood applications, but work great for any battery bank in the back. XS Power has a battery for every form of racing. With a wide selection ranging from 12 pound 12 Volt batteries to 14 Volt batteries for the street to 30 pound 16 Volt batteries. Tested in everything from 300-plus MPH salt flat cars to dirt track to circle track to drag racing to boat racing, XS Power has the only batteries you need for racing. Using the highest energy density chemistry known in AGM batteries, XS Power is now the battery of choice for competition car audio.