The cutting geometry, as well as the shape of the groove, have been developed to obtain an ideal chip sliding; this allows a safe drilling with material difficult-to-machine. The drill is supplied with a TiALN coating which, in addition to increasing the hardness, protects the cutting edges from excessive wear. The drills are available from stock from 0.8 mm diameter up to 3 mm diameter in 0.05 mm sequences divided into two families depending on the depth of the hole to be made; 3 times the diameter for the shorter ones and 7 times the diameter for the longer ones (catalogue). The diameters are supplied standard with a tolerance h5, from Ø 0.8 mm to Ø 3mm = 0 / -0.004 mm