G4623 Drill Bushing Bushing Type Headless Press Fit Inside Diameter 0.136 In Outside Dia 1/4 In Inside Dia Tolerance .0001-+.0004 In Outside Dia Tolerance +0.0013 - +0.0016 In Concentricity Tolerance .0003 In T.I.R. Max Overall Length 1/2 In Material 52100 Thru Hardened Finish Steel Drill Size # 29 Hardness RC 62-64