SD card interface works with FAT16 or FAT32 formatted cards. Built in 3.3v level shifter circuitry lets you read or write super fast and prevents damage to your SD card
Real time clock (RTC) keeps the time going even when the Arduino is unplugged. The coin cell battery backup lasts for years
Included libraries and example code for both SD and RTC mean you can get going quickly
Prototyping area for soldering connectors, circuitry or sensors.
Two onfigurable indicator LEDs
Onboard 3.3v regulator is both a reliable reference voltage and also reliably runs SD cards that require a lot of power to run
Uses the "R3 layout" I2C and ICSP/SPI ports so it is compatible with a wide variety of Arduinos and Arduino-compatiblesHow to use link