HD-660 Professional Monitoring Headphones: The HD660 is a closed-back, circumaural headphone which is excellent for live sound monitoring application because
Specifications: Model : E1Sensitivity:105+/-3dB at 1kHzWireless Range:10meter/33feetFrequency:20Hz-20000HzCharging Voltage : 5VCharging Current : 210mABluetooth Version: 5.0Battery Capacity: 450mAh polymer batteryTalk Time:Up