Features 1、Memory card interface works with FAT16 or FAT32 formatted cards. 2、3.3v level shifter circuitry prevents damage to your memory card. 3、Real time clock (RTC) keeps the time going even when unplugged. The battery backup lasts for years. 4、Included libraries and example code for both card and RTC mean you can get going quickly Prototyping area for soldering connectors,circuitry or sensors. 5、3.3v regulator is both a reliable reference voltage and also reliably runs memory cards that require a lot of power to run. Specification Features: Memory card interface works with FAT16 or FAT32 formatted cards. 3.3v level shifter circuitry prevents damage to your memory card. Real time clock (RTC) keeps the time going even when unplugged. The battery backup lasts for years. Included libraries and example code for both card and RTC mean you can get going quickly Prototyping area for soldering connectors,circuitry or sensors. Works for Duemilanove,for Diecimila, for Leonardo or ADK/Mega or higher.Not supported for ADK/Mega R2 or lower. Specifications: Size: 7*5.4cm/2.8*2.1in Weight: 18g(approx.) Package Includes: 1 x Data Logger Package List