The 100312303 ISO-KF Flange Adapter is used to convert a size NW25 ISO-KF vacuum flange to a 1/4 inch female NPT (National Pipe Taper) standard connection and is made with 304 stainless steel. Flange adapters allow ISO-KF flanges to be connected to other types of standard vacuum components or flanges. Series 31 ISO-KF vacuum components are designed for use at subatmospheric pressure and use standard interface dimensions defined by the International Standards Organization (ISO) allowing them to be interchangeable with other ISO-KF compliant components. Series 31 components can be used as modular building blocks to create vacuum piping systems. IS-KF flanges are "sexless" with a symmetrical seal so that so that components are rotatable. ISO-KF vacuum flanges are joined by inserting a centering ring between the two flange faces, and securing them with a flange encompassing clamp.