... 11/32,3/8,15/32,29/64,31/64,1/2,9/16,5/8,3/4 copper plated steel ... 11/32,3/8,15/32,29/64,31/64,1/2,9/16,5/8,3/4 copper coated steel ... /16" 5/16" 5/32" 7/32" 1/4" 3/8" -7/8" 1/2" 1"4. Hardness: 58-62HRC5. Packing: Bag/Carton6 ... . Brand :Ball king7.MOQ:1 Chemical :ItemC%Si%Mn%P%S%HardnessAISI 10100.08~0 ... 11/32,3/8,15/32,29/64,31/64,1/2,9/16,5/8,3/4, copper steel balls ...