Feature: Hand Free Driving 24Hrs ComfortDesigned for business and drivingCSR Bluetooth chip (V4.1 )Bluetooth phoneBluetooth wireless music transmissionAnswering/ending a callArc line、Rotatable design、 ultra light weight for easy carryingTechnical parameters:Calling time: 4 hoursMusic: 4 hoursStandby time: －250 hoursCharging time 1-2hrs (DC5V)Speaker: 16ΩSNR: -90 dBDistortion: ＋ 0.1%Working Current: 30 mAFile format: MP3 / WAVTransmission distance: ＋ 10 mLi-Battery capacity: 3.7V 80MAHStandby current: <500uA Package include:1xE5 headphone 1x USB charging cable