Hybrid 3 layer Active Noise Cancellation with Active Noise Cancellation. 1. An outward-facing microphone detects external noises and cancels them with equivalent anti-noise. 2. An inward-facing microphone listens within the ear canal for internal noises before producing anti-noise to cancel the left noise twice. 3. Ear caps exclude 90% of noise from entering the ear canal.Transparent Mode allows you to hear what you desire while also allowing you to hear and interact with the environment around you. Without taking off the headphones, you can plainly hear the aircraft or subway announcements as well as what is going on around you.Built-in Dual Noise Cancelling MicrophoneSuppresses environmental noise with a dual microphone noise reduction device. Pairing in a single step When you remove the two headsets from the charging case, they will instantly pair. Then, to link the gadget with your headphones, just activate bluetooth connection on your phone.On-the-go chargingThe TOZO NC9 Plus wireless earbuds can be used for over 8 hours on a single charge and can be charged for an additional 160 hours in the small charging case. Providing an easy way to charge with no strings attached.