I strongly advise everyone to buy version 2 of "Sennheiser Momentum True Wireless". I find it outrageous that version 1 (this one) is still offered at all. An expensive pair of headphones whose batteries drain completely within a few days when not in use (contrary to the official recommendation, this cannot be prevented by switching off the headphones via the app). I don't have to explain what that means for the life of the batteries. In my opinion, they should not be sold like this. Shame on you Sennheiser. (even though the sound quality is outstanding).