Note:Battery is CR1220 3V,we ship without battery! Hope you can understand. Here's a handy a for rduino shield: we've had a lot of people looking for a dedicated and well-designed data logging shield. We worked hard to design an inexpensive, yet sophisticated design. Not only is it easy to assemble and customize, also equipped with extensive documentation and libraries. You can get fast - to save the data to a file in any FAT16 or FAT32 formatted SD card, you can read any drawing, spreadsheet or analysis program. We even have an example of how to use two free software programs to plot your data tutorials Including real-time clock with the current time stamp for all the data so that you know exactly what happened when! Please note that this item does not come with an a for rduino (you need to use the shield), or SD card. It does have the RTC battery, however. Now, the geology of fire to all components of the welding and testing, but not installed head. You need some basic soldering skills to put it together, but even if you do not have much experience, you can within 15 minutes to complete SD card interface with FAT16 or FAT32 formatted card. 3.3V level shifter circuit to prevent damage to your SD card Real-time clock (RTC) to maintain the time, even when the a for rduino is unplugged. Backup battery lasted for many years Including SD card and RTC libraries and sample code means you can get fast Welded joints, circuits or sensors prototyping area. Built-in 3.3V regulator is a reliable reference voltage, and a reliable operation, requires a lot of power to run the SD card Compatible with a for , for Duemilanove, for Diecimila, for or for ADK / for R3 or for higher. for ADK / for R2 or lower is not supported. Color: As Shown Material: PCB Package Contents: 1 * Module Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.