High Speed Steel Jewelers' Bud Burs 2.70-5.00mm These hand-cut, high speed steel burs last longer than standard jeweler's burs. They offer exceptional cutting efficiency and are available in a wide variety of shapes and sizes for cutting most metals. All have 3/32" (2.4mm) shanks and will fit most flexible shaft handpieces. Sizes 10-20; diameters 2.70-5.00mm. Supplied individually.