Dental Carbide Burrs: 1.6mm shank. Made of tungsten carbide for finishing gold, other metals ... Numbers, 220), the green circle, mainly used for scraps of acrylic resin large plates and gypsum. -2. Teeth (ISO ... , in 190), blue circle, mainly used for scraps area alloy and acrylic - resin3. Fine tooth (ISO Numbers, 140), ... precious metals and alloys are used Dental burr made of tungsten carbide material