Buy from Amazon.com : http://fave.co/1CGZr2f
Flashpoint BP960-CA Blast Power Pack Kit for Canon Flashes (Black)
Product Description :
Extra large capacity swappable lithium battery
Dual ports drive two flash units without sacrificing power
LED battery Power Level Indicator on top
Powers most pro shoe mount flashes from Canon Nikon Sony Metz and Quantum Q and Treo flashes
Only 1 second full power recycle with Canon 580EXII Nikon SB900 and Sony F58AM
