The infrared headphones Sennheiser HDI 380 is a nice plus for movie fans who listen closely. Very good sound, while no electromagnetic pollution - in contrast to wireless headphones. At the original battery despite the very high price is no way. My experiment with a cheap replica brought no joy - the thing worked satisfactorily only a few weeks and keeps the headphones now only a few minutes in a good mood. The next replacement battery is original again ...