Empire CPB-400B Cordless Phone Battery 1X3AA/B - 3.6 Volt, Ni-CD 900mAh - Replacement Battery Replacement Battery for Sony BP-T50 - Ni-CD, 3.6 Volt, 900 mAh. 100% compatible with your OEM battery - 3 year warranty. Made with high quality Japanese cells. Synergy Digital is a Registered Trademark