OPTA Wireless Earphone A portable earphone that preventing sweat and rainy High quality sound Ultra-small wireless earbuds, with Bluetooth 4.2 technology Digital noise reduction technology ,can intelligently filter ambient noise and give us clearer sound Created for a positive lifestyle OPTA Wireless Headset is designed for slender and lightweight (15g) while providing a rechargeable treasure function. At the meanwhile,When we do not need to use it,magnetic sticking them together or puting it in a travel bag. Listen for longer time OPTA Wireless Earphone can support up to 10 hours of talk time and 300 hours of standby time, when the battery is fully charged, also can compatible with the iPhone 7 or any Bluetooth device. Controlled by intuition Remote control function by one key allows you to more easily manage - from skipping songs to answering calls but without touching the phone. At the state of multimedia , the main and auxiliary ears both have sound. *Playtime varies according to volume level and audio content. Precautions 1.In the call state, you can hear only from the main headphone. In the multimedia state, you can hear from both of the headphones. 2.When errors (such as pairing is incomplete, there is no sound after pairing, media can not be found, etc.) occur due to system incompatibility, please power off the headphones, clear the Bluetooth records on your phone and try to re-pair. 3.Both the headphones and the power bank use built-in non-removable rechargeable batteries, so do not attempt to remove the batteries so as not to damage the headphones. When you do not use the headphones and power bank for a long time, place them in a dry and ventilated area and charge them once every two months. 4.You can not use the power bank under charging to charge the headphones.