Firstway&reg; Ultra-Slim QI wireless charging module for Samsung Galaxy S4 i9500 i9505 QI card wireless charger receiver INSIDE the battery back case- White Qi compatible wireless charging receiver for the Samsung Galaxy S4 Easy to use,just open the back cover,stick the receiver card to the battery surface,THEN DONE OVER. Slim design to fit inside the back battery,no need to change the phone structure or shape. It`s the receiver only,not included any phone case or QI transmitter pad,needs to buy seperately. Release your phone charging without the cable!And the pad can be universally working for all the phones with QI receivers.Much convinent and popular in our daily life.