· 【Active Noise Cancellation】Hybrid 3 layer active noise cancellation. 1. Outward-facing microphone detects external sounds and counter with equal anti-noise to reduce the environmental noise up to more than 35dB. 2. Inward-facing microphone listens inside ear canal to pick up internal sounds and produce anti-noise again to twice cancel the left noise. 3. Ear caps prevent 90% noise going to ear canal.· 【Transparency Mode】You can hear what you want to hear, which lets outside sound in so you can hear and interact with the world around you. You can clearly hear the announcement of the airline or subway and what is saying around you without taking off the headphones.· 【Type-C Charging Port and Intelligent Protection】Type-C charging port has a reversible design, which means you can plug the cable in either way without worrying about the orientation.When a metal foreign object is detected, the green light will flash, indicating that the device cannot charge the metal foreign object. Note: In order to ensure better and faster charging efficiency, when you use this wireless charger to charge your cell phone, if your cell phone case is too thick, it is recommended· 【Optical Sensors Technology】Features optical sensors technology, they sense when they’re in your ears and pause when you take them out. Adopt high-precision contact sensor, optimized for daily use and sports occasion, achieving real-time detection of wearing status.· 【Charge on the Go】TOZO NC2 wireless earbuds can last for over 10 hours' playtime from a single charge and total 42 hours with the compact charging case after fully charged via wireless charger or USB A to USB C fast charging cable, which can enjoy up to 630 songs on the go. IPX6 Waterproof can prevent from the damage of the splash by sweat and raindrops.