Features:development of software interface for free download, can also be in accordance with the requirements and their modified, download the program is simple and convenient. Can simply use sensors, all kinds of electronic components connection (such as: LED lights, buzzer, buttons, photoresistance, etc.), make all sorts of interesting work.Microprocessor controller, using high-speed development interface and the environment are very simple and easy to understand, very suitable for beginners to learn.Specification:Digital I/O Digital inputs/outputs were：0~13.Analog I/O Analog input/output: 0~5Support ISP download function. The input voltage: when connected to the computer USB without external power supply, external power supply 7 v to 12 v dc input voltage. Output voltage: 3.3 V and 5 V dc voltage output dc voltage output.Package List:1 x UNO R3 Board1 x USB Cable