1. It requires the QI standard charging sender pad to work together to make charging. 2. The phone should be put on the charging sender correctly when charging, otherwise it may fail to charge or charge in low efficiency. 3. It's normal that the pat and your phone get warm when charging. 4. Easy to operate: take off your phone's back cover -- stick the receiver pad to the phone's battery -- close the back cover -- place the mobile phone onto the wirless charging pad (not included).