... and supplied as per the drawings or samples.Grade of the finish ground ballsGradeSizeSpherical deviationLot Diameter VariationAllowable variationNominal ToleranceMachining ... the steel and non-ferrous metal, electric drill for geology use and steel drill etc.YG8K20-K3014.6-14 ... metal, nonmetal materials, drawing of steel, non-ferrous metal and pipes, various drills for geology use, tools for machine Good ...