This is a high-performance replacement cordless battery for the Avaya 9631, guaranteed to meet or exceed the OEM specifications of your original. The cordless battery is 4.47 x 2.46 x 0.8 inches with an output of 3.6 volts. The chemistry is NiMH at 800mAH capacity. Manufactured by Empire Scientific, model number CPH-506. 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.