This is a high-performance replacement cordless battery for the Sony BT1002, guaranteed to meet or exceed the OEM specifications of your original. The cordless battery is 2 x 0.75 x 0.44 inches with an output of 2.4 volts. The chemistry is NiMH at 800mAH capacity. Manufactured by Empire Scientific, model number CPH-516B. 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.