-42dB1 Active Noise Cancellation Tune out the world, remove all interruptions. Take You to the Live Show Spatial Audio2 brings you the 3D sound stage, just like in reality. The 10mm diaphragm unit has the ability to present a much fuller sound. Fast Charge & Longer Playback This device can be fast-charged from 0%-100% in less than 1 hour. Has a continuous playback time of 30 hours. Speed dial number Input your desired contact info in the Baseus App to set up a speed dial number, tap the earbuds' control panel 5 times to speed dial.