Wireless and wired. Child size. Adequate sound.Bluetooth version 5.0Wireless and wired connections Long battery life Built-in 300mAh safe battery, up to 15 hours of lifeWhen there is no power, you can plug in the 3.5mm audio cable and continue to use it.High-quality hidden microphone---Voice calls are clear.Dual volume control to protect children's hearing----85DB/94DBSafe mode----Equipped with volume control function, 85DB to protect children's hearingflight mode---- 94DB solves the noise in the carSkin-friendly material------protein skin-friendly lining, the ear pads are painless to wear and feel like skin, gentle care of childrenHeadphones in foldable design----Lightweight, space-saving, convenient for children to carry when going out.RotatableExpandable soft head beam----Flexible telescopic adjustment, suitable for a variety of head shapes, reducing the load on children's headsHighly compatible with smart devices --- Pad, PC, Phone and so on.40mm diameter speakerCE, RoHs certificateSpecificationName gorsun E66 Wiereless Kid HeadphonesWorking range 12MBattery voltage 3.7VBattery capacity 300mAhBattery charging voltage DC4.2-5.5VCharging time  about 2HWorking time  about 15HImpedance 32ohmSensitivity 85/94DBSpeaker diameter 40MMWeight 190g