InzhiRui Wireless Bluetooth Noise Cancelling Earbuds Headset with Mic, Red The Bluetooth earbud has Hi-Fi Stereo Sound and Built-in HD Microphone with CVC6.0 noise cancellation, ensure clearly Hands-free Phone Conversation or Stereo Music Sound. Our Bluetooth Headsets will comes with 3 different ear tips, please try on each of them until you feel comfortable. The Bluetooth headset built-in 150mAh lithium-ion polymer battery provides up to 150 hours of standby and up to 5 hours of continuous talking / music time with a single charge. Our Bluetooth Headsets can support Say Yes or No to answer or end the phone call. And please make sure there is NOT Aloud Noise while you say Yes or No and dont speak too quietly in case the microphone doesnt receive your voice. Ergonomic Design Bluetooth Headphone, Ultra light weight does not cause any burden to the ear, thus providing lasting wearing comfort and only wear right ear. Here is the steps that how to change the voice language.: A) Keep pressing the power button until the red and blue indicated lights flash alternately B) Press multi-function button twice quickly, then turn off the headsets. C) Keep pressing the power button after the voice language say in English, which means the voice language change successful. 12 months quality warranty, Please feel free to contact us for any product issues. Our Customer Support Team will get back to you promptly. Here is the steps that how to connect with cell phone through Bluetooth Technologies A) Keep pressing the power button until the red and blue indicated lights flash alternately, B) Active cell phone bluetooth, search and connect with the headsets C) The Blue indicated light will flash slowly per 5 seconds after conection successful, the voice will also say connected. And then costomers can enjoy this bluetooth headsets. The bluetooth headphone can compatible with most of Bluetooth devices and connect to two Phones, Extend Range up to 33 FT/10m so you can roam around office or home while on the phone.