UL511 - Ni-CD 3 AA, 3.6 Volt, 850 mAh, Ultra Hi-Capacity Battery - Replacement Battery for Panasonic P-P511, HHR-P402A, N4HKGMA0001, Type 24 Cordless Phone Battery Replacement Battery for Panasonic P-P511, HHR-P402A, N4HKGMA0001, Type 24 - Ni-CD 3 AA, 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