Active Noise Cancellation Hybrid 3-layer Active Noise Cancellation. 1. The outward-facing microphone detects external sound and performs the same anti-noise count, which can reduce ambient noise by more than 35dB. 2. The inward microphone listens in the ear canal, picks up the inner sound and produces anti-noise again, double canceling the left side noise. 3. The ear cups prevent 90% of the noise from entering the ear canal. Transparency Mode You can hear what you want to hear, letting outside sounds in so you can hear and interact with the world around you. You can clearly hear airline or subway announcements and the messages around you without taking off your headphones. Optical sensor technology uses optical sensor technology that senses when they are in your ears and pauses when you take them out. Using high-precision contact sensors, it is optimized for daily use and sports occasions to realize real-time detection of wearing status. One-click pairing Take two earphones out of the charging case and they will pair automatically. Then simply enable the Bluetooth connection on your phone to pair the device with the earbuds.