About this item Bluetooth 4.1 wireless transmission: The reliable and energy-efficient Bluetooth 4.1technology ensures high-quality wireless stereo audio with a range of up to 10 meters. Excellent voice-calling quality and Passive noise reduction function: The hidden omni-directional microphone will automatically pick up your voice with remarkable clarity. With soft earcap design, it can effectively isolate the external noise. With wired and wireless dual modes: http://www.rapoo.com/product/365