This is a high-performance replacement laptop battery for the Acer Extensa 5635Z, guaranteed to meet or exceed the OEM specifications of your original. The laptop battery is 8.03 x 1.89 x 1.02 inches with an output of 11.1 volts. The chemistry is LI-ION at 4400mAH capacity. Manufactured by Empire Scientific, model number LTLI-9231-4.4. 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.