Receive 1 Bluetooth Headphones S560-BlackASIN: B01JOSOOC8 free when you purchase 1 or more this headphones. Bluetooth Headphones S560-Black must be added to the cart. Enter code6WUMKPUAat checkout Noise-cancelling microphone reduces background noise;Fits comfortably in either ear for all day wear . The headset supports a free switch between four languages (Chinese, English, Spanish, and French) ,so as to meet the different needs of customers. Connect Two Devices at The Same Time: Super easy and fast paring with your smartphone or other Bluetooth device;Pair it with two Bluetooth-enabled devices at the same time and don't miss your calls when you have two cell phones. The high-quality 100 mAh polymer lithium-ion battery provides 30% higher performance in Make sure to FULLY charge for the 1st time usage, at least 3 hours. Make sure to pair the headset to the smartphone successfully. Make sure your Bluetooth Headset volume is loud enough,press the volume up key to turned the volume up. Also, make sure the sound volume in the smartphone is loud enough. This is VERY important. Some users complaint about low voice volume because they did not set the sound loud enough.