Grand Cherokee,What is the part number for the part that adjusts the aim of the headlights?

When trying to adjust the driverside headlight the screw spins freely and does not change the aim of the light itself(it works just fine on the passenger side.) I need the part number so I can order or buy the part to replace it. This is for my 2005 Jeep Grand Cherokee Laredo.
The part seems to have the screws inside a small black box that can twist in and out of the socket behind the headlights.

My car has 96800 miles.
My car has an automatic transmission.