My question is this. Im looking at used flash heads at KEH.com and they have a 2100c 2102c and a 2140c. I see these same heads in a 400 w/s 500w/s and 1000 w/s systems. Does the power unit determin the W/S output or is there a different flash units with the same numbers? [img]/ubbthreads/images/graemlins/confused.gif[/img]
