This former allows you to make exact diameter dowels of any timber species you wish. You simply drive an oversized piece of wood through the sharp edged hole of the solid A2 tool steel insert. The 75mm diameter mounting plate has screw holes for permanent mounting (or use it over a dog hole). The interchangeable inserts snap into it securely. Boxed sets of a plate and the four most commonly used metric or imperial inserts are available. The metric set includes inserts for 6mm, 8mm, 10mm and 12mm dowels (imperial 1/4", 5/16", 3/8" and 1/2"). Individual inserts, additional sizes and the mounting plate are available separately.