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.

Double Jacketed Gaskets are used on boiler and heat exchanger applications when ample bolting is available to correctly seat the gasket. They are designed for high pressure and temperature applications up to and inclusive of Class 900. The temperature limitation of the gasket is dictated by the combination of metallic and non-metallic materials used in its construction. Gasket widths as narrow as 8mm (5/16”) can be manufactured dependent on diameter. Very large gasket diameters can also be produced. Nominal gasket thickness is 3.2mm (1/8”). Gaskets can be manufactured with either integral or welded pass partition bars, in a variety of complex configurations. Some of the most common pass bar configurations are shown on the product data sheet hyperlink below.