The CP-E4 Compact Battery Pack is an essential accessory for the photographer demanding faster recycle times and longer Speedlite battery life. The pack takes the optional CPM-E4 rapid-change Battery Magazine that serves as a replacement or backup battery. It can be loaded with 8 AA-size batteries - alkaline, lithium, or Ni-MH. The Battery Pack comes complete with soft case, ideal for protecting and transporting the pack; it also features a belt loop for easy carrying when shooting.
The CP-E4 Compact Battery Pack is compatible with the 600EX-RT, 580EX II, 55EX, 540EZ, 430EZ, MT-24EX and MR-14EX Speedlite flash units.