This kit is for mounting the BXA style Quick Change Tool Post to a HEAVY TEN Inch South Bend Lathe compound. IT FITS ONLY THE HEAVY TEN INCH LATHE. The base is designed to bridge the worn area in the center of most older compounds, and is 2 1/2″ wide to match the Aloris BXA and Phase II 200 series tool posts (and other imports). The base is manufactured from Cold Rolled Steel, and is finished in Black Phosphate, for rust resistance. The bottom of the stud hole has been swaged, to prevent the hardened stud from traveling through the base and potentially damaging your compound. The hardened stud is 5/8″ X 11 TPI, and is left about a half inch long for final fitting to your tool post. The base of the flanged nut is 1 1/16″ for plenty of support. This is a “Plug and Play” tool post clamping system, that will allow you to upgrade your old lantern type tool post to a Quick Change tool holder, and allow a much more rigid cutting tool.