Price / performance is good, but as mentioned by others, at full power only a few trips with lightning are possible - definitely for me a few full-day use and the change is inconvenient.
So I thought I'll get it out a battery pack - the connection is, after all, exist.
I looked first time Amazon was for Walimex Power Pack Connection cable for all "reputable" manufacturers, but not for their own lightning - then looked at Walimex itself time after, not even able to find and decided to write was mich mal support.
Their reasoning was that Walimex device have an own connector (yes, every manufacturer has clearly) and that this would be the reason that you can not offering. Somewhat taken aback, the one manages for any other manufacturer to produce connectors, but not for their own devices prompted me to further e-mails.
It turned out that it even for a single flash of this type of Walimex a possibillity for external power supply are due to the plug !!!
For me more than incomprehensible - possibility is there - it is not used - Due to a plug (plus the own) ???
Thus, the use of the flash does not really enjoy, because you have to carry around multiple batteries / battery packs with them, to make do with long charging times towards the end and must be thoroughly missed good shots when you switch.