Empire BT990 replacement Cordless Phone Battery for Uniden EXS9660, 3.6 Volt, Ni-CD 800mAh Replacement Battery for Uniden BT990 - Ni-CD, 3.6 Volt, 800 mAh. 100% compatible with your OEM battery - 3 year warranty. Made with high quality Japanese cells. Synergy Digital is a Registered Trademark