** Testing conducted by Bose in June 2023 using production-representative Bose QuietComfort Ultra Headphones. Quick charge testing consisted of charging headphones with battery depleted (to the point of no audio playback) for 15 minutes, then resuming audio playback with volume set to a playback loudness of 75 dB, 3-band EQ set to zero, in Quiet Mode (full noise cancellation) with Immersive Audio switched off, resulting in up to 2.5 hours of playback time before battery depletion. With Immersive Audio on, playback time was up to 2 hours before battery depletion. Time to achieve fully charged headphones was determined by charging headphones with battery depleted (to the point of no audio playback) to 100% battery charge.