This is LilyPad Arduino - the main board consisting of an ATmega328 with the Arduino bootloader and a minimum number of external components to keep it as small (and as simple) as possible. Board will run from 2V to 5V. The latest version of the LilyPad supports automatic reset for even easier programming. The back side of the LilyPad is now completely flat! We now use a surface mount programming connector to keep the header from poking through.This version of the LilyPad now uses the new ATmega328 at 8MHz. Arduino 0016 supports the Arduino Pro Mini 328/8MHz. Use this setting when using this new LilyPad 328.LilyPad is a wearable e-textile technology developed by Leah Buechley and cooperatively designed by Leah and SparkFun. Each LilyPad was creatively designed to have large connecting pads to allow them to be sewn into clothing. Various input, output, power, and sensor boards are available. They're even washable!Not sure which Arduino or Arduino-compatible board is right for you? Check out our Arduino Buying Guide!Dimensions: 50mm outer diameter Thin 0.8mm PCB