DROK 090605 DC-DC Buck Voltage Converter 8-22V 12V to 5V 3A USB Step Up Regulator Converting 8-22v to 5V/3A buck voltage power supply board, and 5V USB charger With reverse polarity protection, meaning the module would not burn when wires are connected reversely With apple identification resistance, can support Iphone4, Nokia, HTC, etc There are multiple protections, such as short circuit, overflow current, overheat Synchronous rectification, high conversion efficiency and low heat