Northwestern Bell 39231 Cordless Phone Battery Ni-CD 1X3AA/C, 3.6 Volt, 900 mAh - Ultra Hi-Capacity - Replacement for Rechargeable Battery Replacement Battery for Rechargeable - Ni-CD 1X3AA/C, 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