Features: This R3 board is a optimized version of the original version. It is mainly for customers under the functional requirements for product quality and high case designed both to ensure consistent and compatible with the original, but also easy to use. Completely solve the incompatible and instability problem that traditional 2560 board used for win7 and win8 system. It is the one of the mostly used main boards, completely compatible with the original version. Comes with a USB cable for convenient connection. Specifications: Model: R3 Size: 11*5cm/4.5*2in Cable Length: 55cm/21.7in Weight: 61g(approx.) Package Includes: 1 x Main Board 1 x USB Cable 1、This R3 board is a optimized version of the original version 2、It is mainly for customers under the functional requirements for product quality and high case designed both to ensure consistent and compatible with the original, but also easy to use 3、Completely solve the incompatible and instability problem that traditional 2560 board used for win7 and win8 system 4、It is the one of the mostly used main boards, completely compatible with the original version 5、Comes with a USB cable for convenient connection