Hard Work Sports Bluetooth Headset V4.1 High Definition with Noise Cancelling, Crystal Clear Sound Microphone Hands-Free Calling for iPhone Android Sweat proof, Nano coating enhance durability, moisture resistant Bluetooth wireless headphones Bluetooth wireless headphones with behind-ear ergonomics designed for stability during exercise, running, climbing, skating, fishing, etc. Unmatched performance of extra-long battery and HD built-in microphone allows you to enjoy up to 8 hours of talking and playing time