1. Earphones Wireless specification: V4.2 WT. Support protocols A2DP, AVRCP, HSP, HFP. 2. Transmission frequency: 2.4GHz. 3. Speaker: 14mm. 4. Impedance: 32Ω±15%. 5. Sensitivity: 98db±3db. 6. Audio jack: Lightning-connector. 7. Cable: TPE highly elastic enameled wire. Cable length: 1.2m. 8. Product weight: 10g. 9. Line control supported: intelligent line control (can adjust the volume, previous / next, stop / start, supporting call function). 10. In-ear design, comfortable to wear, not easy to slip off, designed for control of all lightning interface products of iPhone. 11. Support all IOS systems.