Suitable for virtually all thin materials eg non ferrous metals sheet steel plastic or stainless steel for burr free drilling in thin sheet metals without pre drilling for deburring for round holes drilling several diameters with one drill bit enlarging existing holes spiral flute for longer lifetime less vibration and a faster drilling rate diameter mark in both flutes 3 flat shank to prevent slipping in the chuck available in three versions hss 100 service life hss tin