This board allows you to Save all your sensor data to MicroSD card and the included Real Time Clock timestamps all your data with the current time, so that you know precisely what happened when!
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 FOR Arduino is unplugged. The battery backup lasts for years
Onboard 3.3v regulator is both a reliable reference voltage and also reliably runs SD cards that require a lot of power to run