9V Battery DC Jack
This is the 9V to standard 5.5*2.1mm center-positive barrel jack. It is easier to connect and disconnect. You can plug a 9V battery into one end and connect the other end to anything with a 5.5x2.1mm center-positive barrel jack.
Use this cable to battery-power any device that needs 9V and has an on-board barrel jack - it works great for Arduinos, development boards, evaluation boards and more!