Music and two devices
Nothing documents active noise cancellation, control with Nothing X, and simultaneous connection to two devices to switch between laptop and phone.
Case hours also count
The advertised up to 42.5 hours include case recharges and correspond to playback without active cancellation. With ANC, it claims up to 24.5 hours with the case and 5.5 hours with the headphones. These are manufacturer maximums, not guarantees for each situation.
What to check before choosing
Ear (a) and Ear are different models. Check full name, color and condition of the unit. Comfort and insulation depend on the fit of the pads; A sheet cannot guarantee how they will adapt to your ears.