This is a USA Made Armstrong Brand CA Quick-Change Lathe Tool Post that is ideal for lathes with a swing of 14″ to 20″. Tool post is 3.55 square and includes the bottom T-Slot Nut & this nut may have to be machined or replaced, that compound slot nut dimension is not standard on any lathe! You can hold Aloris, Dorian or even import CA type holders on the tool post. This bottom t-slot nut is 2.875″ wide on the bottom portion & 2.010″ on the upper step. USA Made, do not compare to cheap imports! Ever in the Toledo Ohio area? E b a y Stores And check out our website with over 300,000 items in stock! It is fully interactive and will show you current pricing and stock availability on thousands of items! Or register today & open an account to place orders, print statements, expedite orders and more! Also listed will be our toll free telephone and fax numbers for your convenience. Get your copy of our 450 page T&S Catalog, with listings of popular items from all the companies we represent. Direct Links to all our vendors which include some of the top names in the industry; Kennedy, OSG, Guhring, Clausing, Jet, Precision Twist-Dormer, Wilton, Norton, Starrett, Allied, Mitutoyo, YG-1 Keo, Brown & Sharpe and Jacobs, just to name a few! WE SPECIALIZE IN CUTTING TOOLS! Hundreds of decimal reamers, including over and under size metric reamers from 1mm to 20mm….. Hundreds of special taps from #000 to 4, endmills, toolholders, abrasives, fasteners, machinery and much more. Give us a call!