... :2000 certificate 2.Large sales make our prices super low. high precision bearing,ball bearings,roller bearings:A: Inner Ring Bore Diameter ... 618series: 61800-6184011)619series: 61900-6194012)16000series,62200series, 62300series13) Inch series(Rxxx), Metric-Flange(Fxxx, MFxxx), R-Flange(FRxxx),C: Models ... Raw Material: Gcr15 Chrome Steel, Stainless Steel AISI440C, Ceramic Si3N4. high precision bearing