'Drill Bushing, Headless Press Fit, Inside Dia. 1/2 In., Outside Dia. 5/8 In., Inside Dia. Tolerance .0001-+.0005 In., Outside Dia. Tolerance +0.0014 - +0.0017 In., Concentricity Tolerance .0003 In. T.I.R. Max, Overall Length 1 In., Material 52100 Thru Hardened, Finish Steel, Drill Size 1/2 In., Hardness RC 62-64'