The CRL TOYO 48" Self-Oiling Circle Supercutter professional quality tools with a built-in oil reservoir, vacuum cup base, and a graduated pivoting radius bar. The Wheel Unit is self-oiling and swivels 360 degrees in a thrust bearing for accurate and consistent scoring. This cutter allows you to cut circles with diameters up to 48" (1.22 m). For larger diameters, a 36" (914 mm) extension is available for cutting circles up to 72" (1.83 m).