Inner Ring, Bore Diameter 2 1/4 in, Outside Diameter 2.748 in, Overall Width 1.76 in, Ring Material Alloy Steel, System of Measurement Inch, Bore Diameter Tolerance +0.0000/-0.0006 in, Finish Chrome Plated, Lubrication Openings Oil Holes, Outside Diameter Tolerance +0.0000/-0.0007 in, Ring Material Grade 52100, Standards as 9100, ISO Certified 9001, Mil-B-3990 (SAE as 39901)