Features 1、Using bone conduction technology to transmit music through your cheekbones to ensure that your ears are fully open to environmental sounds, making exercise more secure. 2、Bone conduction Bluetooth headset is the highest waterproof grade IPX8, designed for long‑term use in water. Designed for swimming, running, fitness, exercise and other sports. 3、Built‑in 16GB memory, can store about 4000 songs, avoid putting your phone in your pocket during exercise. Can be used as MP3, play songs stored, and listen to songs without a mobile phone during exercise. 4、The earphone transmits sound through the cheekbones, you don’t need to put the earphone in your ear to protect your hearing, you can hear the surrounding sound. 5、Advanced Bluetooth 5.0 earphones connect to your mobile phone or other devices faster and more stable than Bluetooth 4.2. It is compatible with for IOS, for Android smartphone or tablet, PC computer and laptop. Specification Item Type: Bone Conduction Headphones Material: ABS + Silicone Model: K7 Bluetooth: 5.0 Support Audio Formats: MP3, WMA, WAV, FLAC Memory Capacity: 16GB Transmission Range: Approx.10m / 3ft Waterproof Rating: IPX8 Microphone Sensitivity: -37dB Speaker Impedance: 32 ohms Speaker Power: 0.6~0.8W X2 Charging Time: 2 hours (Recharge once a month when idle) Battery Capacity: 350mAh Lithium Battery (shipped with battery) Playing Time: 6-8 hours Package List 1 x Bone Conduction Headphones 1 x Charging Cable 1 x Manual