Cometic Ford SB 289-302/351 Non-SVO Head 4.010in Bore .040in MLX 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. Improved clamp load around the cylinder without increasing bore distortion Requires No Sealants Or Re Torque This Part