1.Material:Gcr15 high carbon chrome bearing steel    (AISI E 52100)

2.Size:2.0mm,2.381mm(3/32"),3.175mm(1/8"),3.5mm,3.969(5/32"),4.763mm(3/16"), 5.953mm(15/64"),6.35(1/4") Gauge: ±12  Subgauge:±0.4             
                 
3.the main steps to produce the ball: heading,polishing,heat treament,grinding,lapping,packing

4.International Standard iso 3290:
VDws:0.25um    Ra: 0.02um

Our factory Standard:
VDws:0.1-0.15um   Ra: 0.011-0.015um

5.HRC: 62-66     6.Noise: 26-30db
7.Precision Grade: G10