Crystal Clear Calls: Utilizes a 360-degree fully open microphone, ensuring clear and crisp call quality HiFi Sound Quality: Employs a composite diaphragm dynamic driver for perfect rendering of high, mid, and low frequencies Pain-Free Extended Wear: Designed with ergonomics in mind, providing a pain-free wearing experience even during prolonged use Plug and Play: Ready for use as soon as it's plugged in, offering convenience and practicality Easy Storage: Comes with a crystal box for convenient and easy storage of the earphones Specification: Model: EM039 Bluetooth-compatible version: V5.2 Transmission distance: 10M Battery capacity: 3.7V/400mAh Running time: 24H Horn parameters: 32Ω±10 Transmission frequency: 2.4GHz-2.48GHz Frequency response range: 100Hz to 20KHz Input port: Type-C Function: Listen to music, call, AUX play Material: ABS Size: 168*184*76mm Executive standard: GB8898-2011  Package included:1 x Earphone1 x Charging Cable1 x English and Chinese User ManualOther items not include