Certification CE ROHS. Tiny earbuds convenient to use Touch control, double keys operation Fast connection with opening case 13mmcomposite membrane driver element Supoort HIFI sound quality CVC penetrating calling Comfort design for ergonmics Materials is ABS PC Wireless solution is Jerry AC6973D4 Wireless version is BT 5.1 Wireless support agreement AVRCP,HSP,HFP,A2DP Transmission distance is 10m Frequency Response from 2.402GHz to 2.480GHz Battery capacity is 25mAh 250mAh The case of charging times for earbuds is 2-3times Frequency Response 20Hz-20kHz Playing time is 4-5h Standby time is 150h Charging time is 1h Color Black white and support customized