Cometic GM LB7/LLY/LBZ/LMM/LGH/LML Duramax .062in MLX Cylinder 4.130in Bore RHS Head GasketCOMETIC MLX (Multi Layer Stopper) gaskets utilize an integrated stopper layer for combustion chamber sealing and improved clamp load around the cylinder without increasing bore distortion. MLX technology can be found in some head gaskets and are made from the same materials as our MLS Head Gaskets. No sealants or re torque required. This Part Fits: Year Make Model Submodel 2006 2016 Chevrolet Express 2500 Base 2006 Chevrolet Express 2500 LS 2006