In short flash of norms. I use a set of 3 pcs + sync. Before that, I took simple ones and itโs easier with them. Here the plus is that the settings from the synchronizer change and you donโt have to go to the flash. I do not know who takes this model. But it is only good in a set of 3-4 of these . One nafig is not needed. Better immediately TTL 685 Summary, take 3 and 6 sets of batteries. And so vpukite)) for a good banquet, one set of batteries is definitely not enough. Will make 300-500 puffs.