Headphone Type: Both left and right ears can be usedBluetooth Version:V5.0 + EDRBluetooth Profiles: Hands free/HeadsetSupporting Agreement: HEP/HSP/A2D/AVRCPTransmission Range: more than 10 metersBattery Type: 55mA rechargeable lithium batteryCharging Time: about 1h-2hWorking Time: Music 4-6 hours (The Volume will affect the time)Standby Time: about 100-150 hoursFrequency Range: 2.40-2.48GHzDistortion factor: ≤1%Frequency Response: 20Hz-20KHzWearing Styles: in-Ear/stealth headphones