size : 1/8" , 5/32", 3/16", 7/32", 1/4", 4mm, 5mm, 6mm MaterialAISI 1010-1015, AISI 1055, AISI1085Size1/8" , 5/32", 3/16", 7/32", 1/4", 4mm, 5mm, 6mmGradeG200, G500, G1000HardnessHRC60ApplicationCycle industryPlackingBulk packing,pounch packing,plastic/tin box packing bicycle steel ball