This is the second version of the 9V to Barrel Jack Adapter. In this version, the material for the 9V battery jack is hard plastic, which makes it 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, centre-positive barrel jack.

Use this cable to battery-power any device that needs 9V and has an onboard barrel jack - it works great for Arduinos, development boards, evaluation boards and more!