... .Reader function: plug in TF card, con- nect to computer by USB 2.0 cable, then download music ... studying material2.Power supply: inlay rechargeable Li battery, use high efficient components, it can work more than 15h ... light flash, it works normal. Red light flash, needs to recharge, after flash 1 min,headset shut off auto. ... after 30s8.OEM are welcome. Foldable&coloful wireless headphone with TF card