Bluetooth Headphones COULAX Bluetooth V4.1 Wireless Neckband Headset in-Ear Sweatproof Sports Earbuds for Running with Mic (10 Hours Play Time, CVC 6.0 Noise Cancelling) TOP QUALITY AUDIO Advanced APTX tech Hear richer and more natural sound from your phone and bluetooth device incredible deep bass sound quality About this product the Battery is 180mAh so the Charge voltage request DC 5v and charging time less 2 hours when customers charge the item please use DC 5V voltage to charge dont use the too high voltage to charge Powerful rechargeable battery provides up to 10 hours of continuous talking/music time with a single charge Bluetooth Headphones should be charged by DC 5V charger If item wont charge please use USB cable to charge item with USB Port Please keep the charge time over 8 hours Dont use other product charge to charging item only use USB port with DC 5V voltage to charge item With CVC6 point 0 noise cancellation technology help to filters out background noise to guarantee high quality sound provides a 5 second stable pairing with your bluetooth device Outstanding connection range of up to 33ft for seamless syncing to your favorite wireless devices Adopt Bluetooth 4 point 1 technology allows these wireless headphones connect with iPhone and iPad Samsung phones and other Bluetooth devices at the same time Please turn off the headphones and delete cellphone pair information Then turn on the headphones to pair again If still cant pair please restart cellphone and charging headphones and then pair them again This item is Bluetooth headphones its a electric product The battery will be damaged by wrong operation please according correct measure to operation products