Inner Ring, Bore Diameter 3/8 in, Outside Diameter 0.624 in, Overall Width 0.76 in, Ring Material Alloy Steel, System of Measurement Inch, Bore Diameter Tolerance +0.0000/-0.0004 in, Finish Chrome Plated, Lubrication Openings Oil Holes, Outside Diameter Tolerance +0.0000/-0.0004 in, Ring Material Grade 52100, Standards AS 9100, ISO Certified 9001, Mil-B-3990 (SAE as 39901)