Tungsten carbide cutters for dental laboratories. Cross Cut fine are for precious metals and ceramics/porcelain; coarse are for Cr Cobalt, precious metals and acrylics; and x-coarse are for acrylics. Plain Cut are for precious metals and acrylics. Black - x-coarse for plastic and gypsum; green - coarse for shaping plastic and gypsum; blue - standard for all dental materials; red - fine for all dental materials; yellow - x-fine for alloys, composites and ceramics.