Simon Birch Bluetooth Headphone S550 Newest Smallest Wireless Invisible Bluetooth 4.0 In ear Music Earphone Earbud Headset Headphone Support Hands-free Calling Microphone for Most Smartphone Built-in DSP audio processing system, can be a very good eliminate Noise and echo, to ensure clear communication, and music. With compact portable design, it is the most mini Bluetooth headset;High performance stereo Bluetooth headset, small, lightweight and stylish. Can connect two device at the same time,the wireless range up to 10 meters. Built-in 50mAh polymer battery.Up to 4 hours of continuous talk time, 3.5 hours of music time. Intelligent voice prompts prompted the state of equipment / to cable.