Namura OEM Style Piston Kit .060 NA-40005-6 fits 1987-1988 Yamaha BIG Wheel 350 BW350 / 1987-1999 BIG Bear 350 YFM350FW 4X4 / 1987-2004 Warrior 350 YFM350X / 2004-2006 Bruin 350 YFM350BA / 2005-2013 RAPTOR 350 YFM350R

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 seizuresMachined 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 pistonsHypereutectic Casting Process - Provides higher silicon content for reduced expansion rates and additional wear resistance; it also has an ability to withstand higher cylinder temperatures