ERGONOMICS DESIGN - The wireless Bluetooth earbud is designed according to ergonomics and the it is smallest Bluetooth earbud in currently, Fits either ear, wear the bud on right ear for better call clarity. ENERGY CONSERVATION - Generally speaking, the battery can keep 2.5 hours life for all kind of this similar products, but our stereo sound wireless Bluetooth headphone has a high capacity battery which 2 times than others. EASY TO CARRY - No wires tangling, and it's easy to storage to your sports armband or package bag. Great for Running, Jogging, Hiking, Biking, Gym etc. Best sweatproof bluetooth ear buds. HIGH QUALITY NOISE CANCELLATION - With outdoor noises reduced, the microphone sound would be clearer as making phone calls. You can enjoy hands-free phone calls with high sound quality even walking on the street. COMPATIBILITY - Can be used with all Bluetooth enabled mobile phones .