The R-Type ring gasket can be ordered to two different profiles, oval or octagonal in cross-sections. Both types have identical pitch diameter as the flange groove they correspond to. These gaskets are used in pressures up to 5,000 PSI. The octagonal type has a higher sealing coeffient than the oval, therefore being the better gasket of the two. The oval type is the only gasket that will fit a bottom radiused groove. Flanges with flat bottom v-grooves will accept either style. Gaskets that have been torqued initiating a metal-to-metal seal should be discarded and not reused.