Arduino Data Logger / Recorder Shield Module Logging for SD Card SD card interface works with FAT16 or FAT32 formatted cards. 3.3v level shifter circuitry prevents damage to your SD card Real time clock (RTC) keeps the time going even when the Arduino is unplugged. The 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. Product Dimensions: 2.1 X 3 X 0.7 inches (6 X 8 X 2 cm) Package Contents: Data Logger X 1, Geekria Warranty