Products

We sell products individually, as well as by the case (5 at a time).

We sell at a different unit price, and only track inventory individually.

Is there a way to create a relationship between two products?

If I have 20 pieces, 4 cases on the shelf --

I'd want the product for pieces to show inventory 20, cases 4.

If I sold a case, I'd want pieces to show 15, cases 3, etc...

Is this possible?