Gikfun USB Nano V3.0 ATmega328 CH340G 5V 16M Micro-controller board For Arduino (Pack of 3pcs) EK1620x3 Operating Voltage(logic level):5V,Support USB download and Power Please wear anti-static gloves or bracelet when operate electronic products.Please keep it in anti-static bag when not use it. Please keep it out of reach of children. Don't use aged usb cable or aged circuit board to connect Nano V3.0 Board.Pull down the usb from computer when no need to upload and download procedures. Suit for people above 18 year's old with 1 year electronic diy experience.Or use it under the guidance of electronic specializer The product is used for learning and test Code.It's Prohibited for any other purpose.