Canon 600EX-RT, 580 EX II, 580 EX, 550 EX, MR-14EX, MT-24EX
YONGNUO YN560IV, YN600EX-RT, YN-560III
The external JJC Flash Compact Battery Pack FB-1(II) improves flash recycle times significantly and increases the number of firings before batteries need to be replaced. The pack can be loaded with 8 AA-size batteries - alkaline, lithium, or Ni-MH - prior to a shoot to ensure fast and smooth transitions from one battery set to the next - important in critical shooting situations or to keep up momentum in the studio. Total minimum flash recycling time can be as fast as 1seconds when used with AA Ni-MH batteries.