Robert Sorby RSTM-CT123 Turnmaster Pack of 3 Tungsten Carbide Cutters: Square, Round and Diamond Set contains 3 different Tungsten Carbide cutters specifically designed to fit the Sorby Turnmaster Set come equipped with one each diamond, square and round cutter Carbide cutters make light work of the tough materials and is extremely hard wearing and long lasting All cutters constructed from micro grade tungsten carbide