Rapoo 2.4Ghz Bluetooth Wireless Headset with Microphone (H6020 Black) Bluetooth 2.1+EDR wireless transmission protocol supports up to 10M (33ft) high-quality, stereo music enjoyment The hidden omni-directional microphone automatically picks up your voice with remarkable clarity Recharge by using the universal mini-USB cable - even while your music is still playing 3-hour charging,12-hour music enjoyment,15-hour calling Your headphone will automatically switch to calling mode when calls coming even if you are listening music Wireless Technology: Bluetooth 2.1+EDR Form Factor: Semi-open