Quality casting and precise machining -- as good as Porsche factory part
With exception of the fact the GMB pump has a cast aluminum impeller, this pump looks nearly identical to the Porsche factory pump (with the plastic impeller). Everything about the material, machining, fit and finish appears equal in quality. I did use a Porsche factory metal gasket, however...as I am not comfortable with the paper GMB gasket. An outstanding deal, at roughly one fifth the cost of a factory pump!