Purity:W>99.98% mainly used to guns, artillery,rockets, satellite, airplane and ship. Grade:W-1Purity:W≥99.98% Appearance:Shine with grey or dark grey metallic luster. Application:Mainly used to found ingredient of material, cutter and heads,tungsten wire for lights instruments and conductor of heat, crankshaft and cylinder barrel of advanced automobile, ingredient of kinds of heat-resistent ...