Type F gaskets are designed to fit the raised face portion of flanges. The outside diameter of the gasket is slightly smaller than the inside diameter of the bolt hole circle. The outside diameter is designed for alignment by the insulating sleeves. The central gaskets are available in the same materials as Type E. Upon installation, it is recommended that tape be wrapped around the outside of the flange to prevent foreign material from lodging between the exposed portions and causing "shorting out" of the flanges.
