This is a high-performance replacement cordless battery for the Sennheiser BA2015, guaranteed to meet or exceed the OEM specifications of your original. The cordless battery is 2.09 x 1.11 x 0.61 inches with an output of 2.4 volts. The chemistry is NIMH at 1600mAH capacity. Manufactured by Empire Scientific, model number CPH-543. 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.