This is a Lithium-Ion Data Battery 7.2V (2190mAh) for use with the GY-HM100/GY-HM150/GY-HM170, GY-HM70U. The remaining battery power by percentage and remaining recording time in minutes can be checked with the touch of a button, even while the camera's power is off. One BN-VF823USP Data Battery can provide a recording time over 2 hours. One of these is included with each GY-HM100/GY-HM150/GY-HM170/ and GY-HM70.