AISI52100 Bearing Steel Ball Material:AISI52100 steel Dia:0.3mm to 200mm Grade:G10 ... ,G40,G60,G100,G200,G500,G1000Application:high speed-low noise bearing,bicycle,motorcycle,automobile,rail,universal ball,bags,electronic industry,grinding other ... contact me directly.Best regards,Helen,Zhang AISI52100 bearing steel ball