HQRP Telephone Battery for Panasonic KX-TG2357 KX-TG2358BX KX-TG5050 KX-TG5230AL KX-TG5248R KX-TG5421 Phone System plus Coaster HQRP&reg; Battery plus HQRP&reg; Coaster; Battery Voltage: 3.6V; Capacity: 850 mAh; Ni-Mh; Nickel Metal Hydride battery pack; Compatible with Original Battery; 1 Year warranty!