Canon CP-E3 Compact Battery Pack for 550EX/580EX

Developed with working professional photographers in mind, the new external compact battery pack CP-E3 improves flash recycle times significantly and increases to approximately 432 the number of firings before batteries need to be replaced. The pack takes optional rapid-change magazines that can be loaded with 8 AA-size batteries prior to a shoot to ensure fast, smooth transitions from one battery set to the next ? important in critical shooting situations or to keep up momentum in the studio. The CP-E3 battery pack is also compatible with the Speedlite 550EX, MR-14EX and MT-24EX.