I need to create something like a TreeView in Excel. I have one list,
the first column is the manufacturer of a product and the second column
contains the various models sold by that manufacturer example:

Manu1 -- Model1
Manu1 -- Model2
Manu2 -- Model1
Manu2 -- Model2
Manu3 -- Model1

I need the user to first select the manufacturer and based on that
selection to select only the model sold by that manufacturer. I do not
want a manufacturer to be displayed more than once nore do I what
spaces in a list. What would be the best approch to tackel this problem
in Excel?

Thanks in advance!