Product Description Ergonomical Design Use the ergonomically designed with gel-flexible silicone earcaps to ensure your In-Ear Headphones fit comfortably to the ears. Both Earbuds are IPX6 Waterproof Protection IPX6 Waterproof Nano-coating efficiently protects the earbuds from sweat or water, perfect for running,skiing, etc. (not for swimming) The 9.2 MM Drive Area is 2.04 times than the Normal Drive Area. TOZO NC9 offers a truly authentic sound and powerful bass performance with 9.2mm large size speaker driver - the drive area is 2.04 times than the normal drive area. One Step Pairing Pick up the two headsets from the charging case, and they will be paired automatically. Then simply enable bluetooth connection on your mobile phone to pair the device with your earbuds. The Most Advanced Bluetooth 5.0 Technology Support HSP, HFP, A2DP, AVRCP. Provides in-call stereo sound. Also own fast and stable transmission without tangling. Easy Touch Control Features with touch control sensors, TOZO NC9 Headset can largely minimize the pressure to your ears when you touch the button for various functions.