Vertex Boring Head Imperial Graduations Photo is of a metric head. They are a quality head.Please don't compare with others. Threaded 1.1/2 x 18tpi Various shanks available in our shop. The item "Vertex Boring Head 3 Imperial Graduations 3MT Shank M12" is in sale since Sunday, February 11, 2018. This item is in the category "Business, Office & Industrial\CNC, Metalworking & Manufacturing\Metalworking Equipment\Machining Centers & Milling Machines". The seller is "fordeight" and is located in West Midlands. This item can be shipped worldwide.