[TripleE]

My adaptive headlights were replaced by warranty a year or so ago. I can check the invoice for any part numbers when I get home.

 

[TripleE]

Land Rover stated that the original part for this (XBC502100L2N) is no longer made and is replaced by XBC502090LN.

My invoice dated September 4, 2008:

XBC502090LZN Headlamp Assy.
XBC502100LZN Headlamp Assy.

So, one if for the left and one is for the right. Don't know what's going on with your part numbers, but I think the "2" in your original part number may be a typo, since it looks like a "Z".