These new precision shower screens are specially designed to improve performance, enhance shot quality, and stand the test of time. They work on all machines that have 58mm E61 group heads (This includes most prosumer/semi-commercial machines from Rocket, ECM, Quick Mill, Magister, Bezzera, etc) The screen gives off an even water distribution, allowing for better extractions, less channeling, precision and more body and roundness in your cup. The NanoQuartz coating on the shower screen is hydro-repellant which ensures that water comes down from the showerhead as tiny drops that disperses evenly through the coffee bed in the portafilter resulting in even saturation. The coating additionally increases resistance to corrosion and chemical reactions from the brewing process.