HQRP 2200mAh Battery for Logitech mm50 Portable Speaker System 970173-0403 S-0173A NTA2335 + HQRP Coaster HQRP&reg; Rechargeable Battery plus HQRP&reg; Coaster; Battery Voltage: 3.7V; Capacity: 2200mAh; Li-Ion; 100% compatible with Original Battery; 1 Year warranty!