Godox Portable Extended Flash Power Battery Pack for Canon 580EX2 Nikon SB900 Sony HVL-F58AM Olympus FL-50R Lithium battery 11.1V /2000mAH Full Power Source: A reliable power source that allows you to create an all-in-one system for extended shooting, fast recycle rates and quick recharging. Fast Recycle Time: Reduces flash recycling time to approximately 1/3 of the original value while the number of flashes increases approximately 3 times. Compatibilities:Canon 580EX II 550EX 540EZ,Nikon SB900 ,Sony HVL-F58AM, Olympus FL-50R Full power flashed:about 900 times