SMAKN&Acirc; SD Card Reader Module Slot Socket For Arduino ARM MCU SD Card module can make your SD application more easier and simple. Can be used for SD Card more eaisly, such as for MP3 Player, MCU/ARM system control. All SD SPI pins output, MOSI, SCK, MISO and CS. Support 5V/3.3V input. PCB Dimensions: 46mm * 30.7mm * 1.6mm.