Certification CE FCC ROHS Battery display on the case 10mm composite membrane driver element Rich and full sound quality with great bass. Comfort design for ergonomics Materials is ABS and PC Wireless solution is Jerry AC6936D Wireless version is BT 5.0 Wireless support agreement AVRCP HSP HFP A2DP Transmission distance 10m-15m Frequency Response 2.402GHz-2.480GHzï¼?RFï¼? Battery capacity 30mAh 300mAh The case of charging times for earbuds is 3times Driver Element Composite membrane 10mm Frequency Response 20Hz-20kHz Playing time is 3h Standby time is 3-4h Charging time is 1h Color Black/white and support customized