I bought the adapter especially for a US flight, because I thought that I might be with my expensive headphones have more fun. Only problem is due to the chunky design fits the adapter does not (at least at Lufthansa) in the socket, even turning etc. has brought nothing. Was come, that I was bent by the try out one of the plugs. On the flight back to me is to use the adapter when trying fallen apart the thing.
Conclusion: Had but the headphones Lufthansa take, fortunately this is to cope with this price.