Features:This is a economical, powerful, easy-to-use mechanical arm learning kit.Ideal robot arm DIY assembly kit for college students, middle school students, DIY enthusiasts, etc.4 degrees of freedom robot arm with more untrammeled and flexible experience.The control board adopts for original edition, and there are numerous learning materials in the network.After connecting the computer with USB cable, you can send commands through the serial port to control the movement of the arm.It is also compatible with other control software, and supports writing your own programs to perform invariable and repeated actions.Specification:Model: SNAM1900Power Adapter Plug: US 100-240V Material: Acrylic Weight: Approx. 530g/18.7ozPackage list:1 * Set of Acrylic Cutting Parts + Screws1 * Development Board1 * Potentiometer Control Board (need to solder by yourself)1 * Power Adapter 5V/2A4 * sg90 ServoNote:Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering..