Panasonic KX-TG2740 Cordless Phone Battery 3.6 Volt, Ni-CD 850mAh - Replacement For PANASONIC P-P511, TYPE 24 Cordless Phone Battery Replacement Battery for PANASONIC P-P511, TYPE 24 - Ni-CD, 3.6 Volt, 850 mAh. 100% compatible with your OEM battery - 3 year warranty. Made with high quality Japanese cells. Synergy Digital is a Registered Trademark