iPod® Replacement Battery Many iPod® replacement batteries make incredible capacity and runtime claims. After a year, most batteries are so degraded they barely provide enough power to run your iPod®. Personal digital devices demand pulse power from the battery. Ordinary batteries are damaged easily by these power demands decreasing capacity, runtime, and battery life. Within six months,runtime can be cut in half, and in a year your iPod is rendered practically useless. Big Wave Power's patented nanotechnology device is different. It provides for the pulse power demands allowing the battery to run smoother and cooler. Because of this, Big Wave Power's iPod® batteries degrade at a much slower rate. The big wave iPod® battery replacement not only lasts 3 or more times the number of recharges, it retains more of its charge over an extended period of time. FOR GENERATION 4 iPods® Battery Does not fit MINIS, NANOS and SHUFFLES