The Cometic MLX head gasket for Hemi Gen3 Iron Eagle blocks with a 4.150 in bore (LHS) uses an integrated "stopper" layer to seal the combustion chamber. MLX construction increases clamp load around the cylinder without adding bore distortion, providing the sealing characteristics expected where the 4.150 in bore and left-side gasket are specified.
Cometic Hemi Gen3 Iron Eagle Block .054in MLX Cylinder 4.150in Bore LHS Head Gasket