These Centering ring Nozzle vacuum fittings are compatible with flange size ISO-KF NW-40. These nozzles are designed to reduce and direct flow in your vacuum system, allowing for better process control and analysis. When coupled with a standard O-ring, this component can be placed at any location in your system where a standard centering ring would normally be seated, facilitating simple system upgrades. Fittings are manufactured from corrosion-resistant stainless steel.