Two spiraled main cutting edges in fully ground quality with stepped cylindrical shank Ø 13 or 16 mm, Milling of slots in soft wood and limited in European hard wood with a slot drilling machine. Higher cutting rate and ideal removal of the chips due to the twisted geometry of the main cutting edges. Thanks to the twisted spiral this drill runs particulary smoothly and without any annoying chattering. Alloyed tool steel 2500 - 5000 rpm. e.g. Ø 16 mm 2500 rpm in soft wood.