This is a high-performance replacement cellular battery for the Samsung AB533640FZBSTD, guaranteed to meet or exceed the OEM specifications of your original. The cellular battery is 1.63 x 1.55 x 0.21 inches with an output of 3.7 volts. The chemistry is Li-Ion at 880mAH capacity. Manufactured by Empire Scientific, model number BLI-1030-.8. 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.