This cable has a male USB A plug on one end and a DC 3.5 mm x 1.35 mm barrel plug, center positive on the other end. The length of the cable is about 1.5 meter.

This cable is handy if you want to power a device with barrel jack from a USB port. A USB port typically delivers between 4.75V to 5.25V DC power.

We powered an external hard disk with this cable plugged to a USB power supply.