Designed to add additional shooting time versus just using the battery in the camera alone. The MB-N10 is a Multi Battery Power Pack for the Z 7 and Z 6 full frame mirrorless cameras (cameras sold separately). The MB-N10 may increase the length of shooting time up to 1.8x more than using just the camera’s battery. The MB-N10 is designed with the same weather sealing and modern design of the Z cameras and affords photographers a well-balanced feel when a long telephoto lens is on the camera. The MB-N10 can accept two EN-EL15b or EN-EL15a/EN-EL15 rechargeable Lithium-ion batteries each housed in its own battery compartment. For convenience the batteries are hot-swappable which means that you can replace one while the other continues powering the camera. This is beneficial for video interval and time-lapse shooting. With two batteries power is first drawn from the battery in chamber A until it is depleted and then the unit draws power from the battery in chamber B. Compatibility: Z 7 Z 6