Namura, NA-50025K, Namura Piston & Gasket Kit Polaris Magnum 330 Standard Bore 78.5mm MOS2 (Teflon/Molybdenum) Coated Skirts A rolled on application process provides a bond that is 10 times stronger than other spray on coatings. Benefits include increased heat transfer, reduced friction and helping to eliminate cold seizures. Machined Smooth Heads Reflects combustion heat and reduces carbon buildup, protecting the top of the piston. Some tests have shown this feature can increase horsepower and fuel economy by up to 6% Anodized Domes Increases heat resistance and durability; pistons with anodized domes are 75% stronger than non-anodized pistons Hypereutectic Casting Process Provides higher silicon content for reduced expansion rates and additional wear resistance; it also has an ability to withstand higher cylinder temperatures