Just how big is that driver?

hi All,

I'm wondering just how to measure drivers physical dimensions. Are drivers measured only to the surrounds inner perimeter? Or, in other words, are they in fact measured to the overall extension of only the material making up the cone itself, and NOT the surround/supportive construct?

Or, in fact, is it�s actual dimensions, the whole overall exposed, structure, right out past the screws holding it to the baffle?

To my way of thinking, a cone or dome driver's size is just that part up to but not including the surround, if any, regardless the actual materials being used.