The filler material is completely enclosed by a two piece metal jacket, which covers both the inside and outside diameters and both contact surfaces. Style 126 is similar to Style 123 with the exception that the metal jacket is formed from a corrugated jacket providing better resilience than the Style 123, since the corrugations form multi-seals across the flange sealing face. Style 127 is a double shell gasket constructed of two reversed wrap-round shells. This provides handleability and better resistance to high pressures.
