This is a high-performance replacement tablet battery for the BARNES AND NOBLE  NOOK HD 7, guaranteed to meet or exceed the OEM specifications of your original. The tablet battery with an output of 3.7 volts. The chemistry is LI-POL at 4000mAH capacity. Manufactured by Empire Scientific, model number TLP-049. 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.