With built-in 10mm aperture drivers our i9s Bluetooth earphones deliver superior sound with powerful bass, clear vocals, and crisp high tones.One-Step Pairing Bluetooth Connectivity: When you take your earbuds out from the charging case, your HSPRO earbuds will power on and pair automatically, simply select bluetooth name on your phone to pair for the first time. Now with Bluetooth 5.0 technology that ensures fast and stable connections, as well as low power consumption and latency.