Bluetooth headphones, Wireless Ergonomic Earhook Design headset for sports&Running, Stereo Earphones with build-in Microphone Sweatproof and Noise Chancelling, Bluetooth 4.1 for smartphones (4) Bluetooth 4.1 version: Easy and fast pairing with smartphones, tablets and other Bluetooth enabled music devices. Ergonomic Earhook design and intelligent noise reduction make it stable & comfortable for use in sports/running/gym/exercise and other outdoor activities;With Ergonomic design and silicone ear hooks, Magicbuds Bluetooth Headphones are secure behind your ears and rest comfortably in the ear canal. Premium soft smooth silicone gel surface helps sweat proof. It is great for Gym, Running, Jogging, Hiking, Cycling, and impact Sports. Build-in Microphones Sweatproof you can enjoy music & calling/answering phones hands free. Built-in battery  allows about 3 hours calculating conversation and playing time, and 100 hours standby and only 1-2 hours charging time RF Rang :10meters. And it is universally compatible with most Bluetooth-enabled smart phones