Below is a general manufacturer product group description. Please note the information below is not item specific. Item specifics are above in product details.

NOTE: COMPRESSION RATIO’S LISTED ARE FOR COMPARISON PURPOSES ONLY, ACTUAL RATIO ACHIEVED MAY VARY DEPENDING ON APPLICATION.
HKS metal head gaskets are engineered to resist severe levels of heat that are generated by high-horsepower and high-boost applications. All HKS head gaskets are constructed with multiple layers of steel and coated with a special fluorine rubber to provide exceptional sealing. HKS head gaskets are designed to accommodate standard and certain oversized cylinder bores.
For most applications, multiple gasket thicknesses are available to change the dynamic compression ratio for various levels of tuning and engine conditions. (Note: HKS gaskets are not designed to cure sealing problems caused by head or block irregularities.)
The HKS Stopper-Type gasket consists of the maximum layers of plates possible and utilizes a molded stopper ring around each combustion chamber opening.
The HKS Bead-Type gasket features a raised bead structure around each combustion chamber to ensure a precise seal.
The HKS Grommet-Type Gasket employs a metal grommet around each combustion chamber, to ensure an excellent seal between the cylinder head and the engine block.