Features Precision High Quality Double Bearings Live Revolving Center Centre Body is made from Alloy steel grade of EN8D and EN31 is used for Quill/ Point Center Used quality Z type bearing (covered), so that the grease inside when melt at high temperature during working will remain locked and sealed. The body ID(s)/ bearing casing of the Revolving Centers are internally grounded who only provide machined ID(s). This grinded inside body gives best control on the run out after bearing and quill fitting.