Dorian Extra Heavy Duty Broing Bar Holder DA-41 D50DA-41 Max Shank size 1.745. Ajax E-Bay store supplies the full line of Dorian Products. Need any help looking please call. The item "Dorian Quick Change Extra Heavy Duty Boring Bar Tool Post Holder DA-41 NEW" is in sale since Wednesday, November 11, 2015. This item is in the category "Business & Industrial\CNC, Metalworking & Manufacturing\Workholding & Toolholding\Toolholding\Quick Change Tool Post". The seller is "ajaxtoolsupply" and is located in Columbus, Ohio. This item can be shipped to United States, Canada, ...