Ultra-fast service, order placed on Thursday evening, flash received Monday noon ... Tracking package in real time, what more? The 568 EX II flash works fine for now, its two initial design flaws (weak battery hatch and failure of some sub-models that expose -2 IL evaluative mode) seem to have been resolved and my model is not reached by these two défaus. Powerful, reliable, it is recognized by my camera 1D Mark III as if it were a 580 EX II or a Canon 600 EX. we can then use it in master mode to trigger other flashes Nikon or Canon slaves. In short, I recommend it!