These are Marshall Motif II A.N.C. earphones with active noise cancellation and 30 hours of wireless playback. - Brand: Marshall - Model Name: Motif I A.N.C. - Features: Active Noise Canceling - Wireless: True Wireless - Playback Time: 30 hours After some use, a high-pitched noise started coming from the left earphone. I have tried a hard reset of the unit. The right earphone and the case are working normally. Please understand this before purchasing. Please refrain from purchasing if you are concerned about the fine quality condition. Thank you for viewing.