at-T/Lucent E5965C Cordless Phone Battery Ni-MH, 1.2 Volt, 2600 mAh - Ultra Hi-Capacity - Replacement for Sony BP-T31 Rechargeable Battery Replacement Battery for Sony BP-T31 - Ni-MH, 1.2 Volt, 2600 mAh. 100% compatible with your OEM battery - 3 year warranty. Made with high quality Japanese cells. Synergy Digital is a Registered Trademark