1/2 diameter boring bar holes. Includes 1" diameter x 1.5" long shank with flat for weldon holder. This item is in the category "Business & Industrial\CNC, Metalworking & Manufacturing\Workholding & Toolholding\Toolholding\Adapters & Holders\Boring Head & Adapters". The seller is "prairiewestdesign" and is located in this country: US. This item can be shipped to United States.