Sony BP-T16 Cordless Phone Battery 1X3-2/3AA/B - 3.6 Volt, Ni-CD 400 mAh - Cordless Phone Replacement Battery Replacement Battery for At&t/Avaya 2C1 - Ni-CD, 3.6 Volt, 400 mAh. 100% compatible with your OEM battery - 3 year warranty. Made with high quality Japanese cells. Synergy Digital is a Registered Trademark