Battery type: Li-ion; Capacity: 2600mAh; Cells: 4-cell; Voltage: 14.8V. Compatible Models: D550 X451 X451C X451CA X45Li9C X45li9c X551 X551C X551CA X551CA-0051A2117U X551CA-DH21 X551CA-SX024H X551CA-SX029H X551MA