Drill Bushing Bushing Type HL Head Liner Inside Dia 1-3/8 In Outside Dia 1-3/4 In Inside Dia Tolerance +0.0006 +0.0010 In Outside Dia Tolerance +0.0019 +0.0023 In Concentricity Tolerance .0005 In T.I.R. Max Overall Length 1-3/4 In Material 52103 Thur Hardened Drill Size 1-3/8 In Hardness RC 62-64