Cometic GM LB7/LLY/LBZ/LMM/LGH/LML Duramax 4.130in Bore .062in MLX Head Gasket LHSThe HP shim technology increases clampload around the combustion chamber, thereby increasing the sealability of the head gasket around the open deck block. Improved clamp load around the cylinder without increasing bore distortion Embossed Outer Layers Coated w Viton This Part Fits: Year Make Model Submodel 2006 2016 Chevrolet Express 2500 Base 2006 Chevrolet Express 2500 LS 2006 Chevrolet Express 2500 LT 2006 2016 Chevrolet Express 3500 Base 2011