This is a high-performance replacement laptop battery for the IBM FRU 42T4502, guaranteed to meet or exceed the OEM specifications of your original. The laptop battery is 8.1 x 3.13 x 0.83 inches with an output of 10.8 volts. The chemistry is Li-Ion at 6600mAH capacity. Manufactured by Empire Scientific, model number LTLI-9010-6.6. We offer a 1 Year Warranty with purchase. See this product elsewhere at a lower price? Call or email us; we have a Price Match Guarantee.