1.material:AISI1010-1015 2.size:1/4",3/16",6mm.6.33mm,6.5mm 3.grade:G1000 4.standard: ISO9001:2008 5.inspection & warranty Namecarbon steel ball for curtainSize1/4",3/16",6mm.6.33mm,6.5mmGradeG1000Quality standardISO9001:2008FeatureGood wearing, excellent surface, best quality and high hardnessApplicationMainly used for simply bearing, curtains, castor wheel, bicycle, aviation and so onPackage1) ...