DigiYes&Acirc; DC5V / 2.1A Cylindrical Vehicle Wireless Charging Transmitter for the Qi Standard Cell Phone Receiver, Such as Samsung Galaxy S3, S4, Note 2, Note 3 Once you put this QI-marked charging machine in the charging area , it will start to charge persistently. This QI-marked products,fits the wireless charging standard set by the WPC. This product also can charge the charging machine which consist of QI-marked power plug and charging machines .(There are conditions that this product does not charge well for some machine please read the operation manual carefully before using it .) This product is designed for vehicle users. It is very convenient and useful to charge your mobile phone while driving. Followed by WPC Qi standard wireless charging specification, it applies for all the Qi compatible receivers. Meet up with WPC_QI standard wireless charging pad . It can make your phone charging safely and stable while youre driving.3-colis one to one wireless charging , no need to look for the charging position any more.