HQRP Battery for TomTom Start 45, Start 45M, Start 55, Start 55M 6027A0090721 1EF0.017.03 1ET0.052.09 4EF0.017.00 4EF00 GPS Navigator + HQRP Coaster HQRP&reg; Rechargeable Battery plus HQRP&reg; Coaster; Battery Voltage: 3.7V; Capacity: 950 mAh; Li-Ion; 100% compatible with Original Battery; 200 Days warranty!