Godox PROPAC PB960 Dual-Output Speedlite Power Battery Pack 4500mAh for Canon Nikon Sony Metz Flash Black Large-capacity lithium battery (11.1V/4500mAH), it takes only one second to charge Canon 580exII, Nikon SB900 and Sony F58AM flashes at the maximum power, supporting about 1800 times of flashes. Dual outputs for powering two separate flashes without reducing recycle time. Optimized MCU circuit design, more efficient energy conversion and more flashes. Battery chamber replaceable and removable from the entire unit, if you buy an additional battery chamber for replacement. Ship From USA, 2-5 Business Days Fast Delivery