Material:Gcr15 high carbon chrome bearing steel    (AISI E52100)

Grade: G10    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: ±12um  Subgauge:±0.4um         
                    
the main steps to produce the ball: heading,polishing,heat treament,grinding,lapping,packing

the special and and fine producing-technique;the tiptop production equipment,like:super-fine dringding machine from Germany,resin super-fine grinding machine from Japan; the precision test equipment,like:automatic stee-ball shape tester,Single&Double-view metalloscope,Rockwell & Vickers hardness tester,stee-ball vibration measurer,roundness meter and etc;and an appropriate scale of operation                           

the product is: possible hardness, technical characteristics,perfectly shiny, compact and defect-free surface,low noise

HRC:62-66
Noise: 26-30db
VDWS: bellow 0.15um