This OE quality air conditioning expansion valve is vehicle specific and a direct replacement for the original component. Rein automotive products provide you with the proper fit, form and function for European vehicles. With fitments for some of the world's finest automobiles, including Audi, BMW, Mercedes Benz, Mini, Porsche, Saab, Volkswagen. Since the air conditioning system is a "closed loop" system there is not a way to check and see if everything is working properly until the parts are replaced and the system is fully functional again that is why Rein air conditioning products are built to the exact original manufacture tolerances and when applicable pressure tested before leaving the factory..