Energizer ER-P510 Cordless Phone Battery Ni-MH 1X3AAA/D, 3.6 Volt, 800 mAh - Ultra Hi-Capacity - Replacement for Rechargeable Battery Replacement Battery for Rechargeable - Ni-MH 1X3AAA/D, 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