This is a simple cable that adapts from a USB port to a 5.5×2.1mm barrel connector, center positive. This cable allows the user to use a USB port on a computer, laptop, or on our cigarette power supply to provide our development boards with 5V. The USB specification limits current consumption to a max of 500mA from a USB port but this is more than enough to run a simple development board. Cable length is approx. 1 meter. Technical Details Input Voltage 5 VDC Length : 1 meter Plug A: USB-A Plug B: 5.5×2.1mm