SD card module is a very simple solution to add memory to your Arduino project to store the data, media, transfer data, etc. It is also called a micro SD adapter which is designed for dual I/O voltages. The pinout of the module is directly compatible with Arduino as well as other microcontrollers. The device has an SPI interface that is compatible with any SD card and it uses 3.5V and 5V power supply which is compatible with Arduino UNO/MEGA. 
Features
Supports micro SD card (<=2G), Micro SDHC (<=32G) (High Speed Card)
The level conversion circuit board that can interface level is 3.3V and 5.5V
Directly compatible with Arduino or other microcontrollers
SPI communication method
Specification
Operating voltage: 4.5V to 5V
Communication interface: SPI
Control interface: GND, VCC, MISO, MOSI, SCK, CS
Supported SD card: 2GB to 4GB