Use 9V Battery Snap Connector to connect a 9V battery to anything with a 5.5×2.1mm plug. This Snap Connector is useful to power-up development boards (like the Arduino) with a 9V battery. The cable has a molded 5.5×2.1mm plug on one end, and a 9V battery snaps on the other. The battery snap covers the battery contacts to prevent shortcircuits, and it’s made of plastic, so it is more durable than traditional clips. The polarity on the plug is positive at the center. 9V Battery Snap Connector to DC Male Power Adapter Cable for Arduino.
1 x 9V Battery Snap Connector to DC Male Power Adapter Cable for Arduin