Enhanced Bluetooth 5.0 and CSR chip. Ugreen makes music playback and calls smoother and clearer than ever before. Make your lifestyle cool with Bluetooth 5.0. The built-in microphone makes conversations with family and friends a breeze. Perfect for hands-free calling while driving. Thanks to the hands-free feature, you can focus on driving. With the user-friendly receiver, you can connect two mobile phones simultaneously and easily switch between music and calls on either device. With up to 10 hours of talk or playtime or 120 hours on standby, you have enough battery power to last through even the longest family outings.