B220SL4AC - Aluminium Cut Carbide Burs Taper Shape 1/4? Shank Taper Shape Carbide Burs The chisel tooth pattern not only minimises tool chatter but reduces the chip to a granular shape, in most materials. Al Cut for rapid material removal of soft materials such as: Aluminium, Brass, Copper, Plastics that would normally load other cuts Shank 1/4 Length 2 7/8 / 73mm Diameter of Head 1/2/12.7mm Length of Head 1 1/8 / 28.6mm