Bluedio Q5 Bluetooth 4.1 Ultralight Mini Sport Headset In-ear Stereo Earphone (light blue) Ultra-low Power of the latest Bluetooth 4.1 doublesplaytime to a solid 7 hours. Unique ear tips(S/M/L size included) help to keep the earbuds in your ears. Plus the control unit is lighter and smaller, no pulling at workouts. Built-in Mic can be used for clear phone calls, never miss a call when enjoying music you love. Compatible with most of the smart cell phones,computer and other device which has bluetooth function. The earphone is sweatproof,can not use for swimming.