... 1.6mm shank. for finishing gold, other metals and acrylic plastic materials. Dental Carbide Burrs:1 ... , 220), the green circle, mainly used for scraps of acrylic resin large plates and gypsum. -2 ... Numbers, in 190), blue circle, mainly used for scraps area alloy and acrylic - resin3. Fine tooth ( ... ISO Numbers, 140), red circle, the Lord for scraps fragile and difficult to scurf cemented carbide, acrylic ...