This adaptor allows you use your favoriate headphone on airplane.

Amazon.com

Tired of relying on the cheap, plastic headphones the airlines give you during your flights? Ear Hugger can help! With the Ear Hugger EHA-18 Airline Headphone Adapter, you can use your own set of headphones on any airline that uses dual 3.5 millimeter headphone jacks. Just plug the adapter into the airline socket, and you can enjoy your movie or music with the comfort and performance of your own set of headphones.