Maxtop isothermal grading quenching oil is made of highly refined mineral oil as base oil, adding a variety of high quality and efficient additives such as antioxidant and coolant, through a unique formula. It is a kind of high performance cooling medium specially designed for metal heat treatment process, mainly used for steel, alloy and other workpiece quenching processing. By precisely controlling the cooling speed, it can achieve the classification effect of “fast cooling – slow cooling” during the quenching process, which not only avoids deformation and cracking of the workpiece, but also ensures the best balance of material hardness and toughness.