This is an OE quality receiver drier. If the OES manufacturer fits a high pressure safety valve and or sight glass, the equivalent Rein Automotive Receiver Drier will also be fitted with one. All Rein Automotive Receiver Driers are pressure tested after manufacturing to ensure high quality. 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, and Volvo all Rein Automotive genuine replacement parts are guaranteed original manufacturer quality. 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. This guarantees that they work the first time they are installed.