This connector converter can convert a 7.9 x 5.55mm male connector with center pin to a 5.5 x 2.1mm male connector.
The back end of this converter is a 7.9 x 5.55mm female jack:
It can plug to a 7.9 x 5.55mm male connector, convert it to a 5.5 x 2.1mm male connector like this:
Note: 7.9 x 5.55mm connector with center pin is widely used on IBM/Lenovo laptop power adapters.
Overall Rating for Y62 Power Connector - 7.9 x 5.5mm Female Jack to 5.5 x 2.1mm Male Plug