I purchased 3 of these on special offer.They seem to work great for the price, transmission range is excellent easily exceeds 10 metres range.The only minor issue I had was that one was in English and the other 2 were set to Chinese by default. This is easily resolved though! 1. Turn off Bluetooth on your phone.2. Place the Bluetooth Ear piece in your ear and turn on by pressing the silver button for 3 seconds. 3. Press the silver button twice to toggle language between Chinese and English.