This adapter has a female Type C USB plug on female on one end and 5.5mm x 2.1mm DC barrel plug on the other end.

It is handy if you have USB-C DC power supply and you want to power a device with a DC barrel jack.

Take note that this adapter does not do any voltage conversion. Most, if not all USB powered devices runs on 5V, be mindful of the voltage that you connect to the barrel jack.

Disclaimer:

Use at your own risk. Always check the voltage with a voltmeter and make sure your device can handle the power that you are connecting it to!