... Frequency response: 20Hz to 20000HzInterface: 1*Mini USB 2.0, 1*3.5mm earphone jack,1*DC jack, 1*TF card slotIn/Output :input ... . Normally, the process of checking Mobile Phone is as follows:1.Functioning Test: Outlook, Calibrate screen, Keyboard, WIFI, Camera, all ... Battery, USB Cable, Earphone, Charger, TF cardPayment:We accept payment via TT (Bank transfer), Western Union, credit card.We accept bank ...