Spare VB-18 Li-ion battery for VING V850 and VING V860 speedlites. Capacity is equivalent to that of 6 to 12 NiMH batteries and is quick and easy to install and is convenient to carry. Provides 650 full power flashes, which is up to 5x more power than you get from four AA batteries. At full charge, you get a fast recycle time of 1.5 seconds and 200 full power flashes before any drop in recycle time becomes noticeable. Battery recharge time is just 2.5 hours.