Wire seal flanges are sexed—with malefemale flanges forming a mating pair that captures an OFHC copper "o-ring" gasket under extreme compression. The material of choice is 304L stainless although 316L stainless may be available as a custom material. The flanges' design constrains the gasket's flow to form a seal between them. Wire seal flanges can be used over the same temperaturepressure ranges as CF flanges. They are used where tube dimensions exceed those of standard CF flanges.