Bengoo Wireless Universal HandsFree 4.1 Bluetooth Headset Headphone Earphone [Built-in microphone] - Yellow Chip: Chipset Bluetooth V4.1 Breakthrough exclusive technology, playtime to a 4 hours. Use your music device left/right side. Fully exercise-proof: with functional user interface, earpiece design, and a 10-meter working distance, our headphones will let you enjoy music through a variety of activities. Universal device compatibility: the Kinetic Series Headphones are compatible with most Bluetooth-enabled phones, and reduce external sound. Simple-to-use: control all functions of your music (volume, sound) and calls from your phone via our simple-to-use user interface on the headphones themselves. Durable design: Up to 4 hours of Talk/Playing Time and 175 hours Standby Time. High-fidelity stereo music and clear speech, You can begin enjoying CD quality stereo sound instantly.