AUX Audio Adapter Splitter Dongle Music Audio AUX Accessorie Headphone Adapter Headset Audio Adaptor Connector Earphone Ultra fashion, compact and light-weight design for comfortable fit Has Mic mute feature,when you press and hold Decrease Volume Key (-) for 2-3 seconds will hear "DuDu" tone prompt to turn on/off Mic during the calling. Over-the-head design with booming MIC .Work with most of BT enabled phones . If there is any issue with BT, customers need to ensure the headset has enough power,is turned on and has been successfully paired to the device. Talking/Standby time: up to 8 hours/Up to 200 hours Superior Noise Cancellation technology (crystal clear conversation) .If the voice gets muffled, Please check that whether the range between the headset and the mobile is over 10 meters,or there is wall or other disturbance or other electrical devices between headset and mobile.