Bluedio T2s Bluetooth Headphones On Ear with Mic, 57mm Driver Rotary Folding Wireless Headset, Wired and Wireless headphones for Cell Phone/TV/PC, 40 Hours Play Time (White) Great SoundBluedio engineers have spent two years in creating T2S Ultra-big speaker, diameter up to 2.24 inches, trying to bring you the best music experience: rich and strong bass, crisp and clear highs. Connectivity Technology: Wireless Bluetooth/WiredT2S is not only a Bluetooth headset, but also a wired headset. With the included cable, you can still enjoy favorite music when the battery runs low. Bluetooth 4.1 ChipIt's the latest Bluetooth chip, which can transmit data at high speed and bring you smooth music experience. And its low power ensures long lasting battery life: up to 40 hours continuous music time. Comfortable to wearIts ear cup and headband top are padded with sufficient foam and covered with soft leather. What you may not notice is that we have adjusted the headband, based on Ergonomics theory, to fit all head sizes. Cool LookT2S, T is the abbr. for Turbine which we think can best stand for your endless passion and energy. And T2S is rotary, you can rotate the ear cup up to 195 Degree, easy to carry and save more space When the headset is off(if not, power off the headset first), press and hold the MF button, only when the LED remains blue can you release the button. The headset is in pairing mode. Switch on the Bluetooth of your mobile phone, add/search devices. When &#039;Bluedio&#039; appears, select it. (If asked for a pass code: Enter &#039;0000&#039;)