... .Hardness:HRC58-61 3.High precision,ABEC-1,P0 3/16 inch ,4.763mm ball bearing steel balls,used for bearings ABEC ... -1,P0 high precision ,good quality ,fast delivery timechrome ... bearing steel ball1)material:AISI52100 GCr152)Size:1/8",1/4",3/16",5/16",5/32 ...