Specially formed channel for removing chips, teflon-coated, changeable crest of thread HSS, two carbide tipped main cutting edges, protruding cutting edges and cylindrical shank with three clamping surfaces. Ground by diamond wheels on CNC-machines. For drilling precisely fitting holes in hard wood. For exotic hard wood like Bongossi we recommend auger bit product line 1493. Also applicable with a powerful joinery machine for drilling end-grained hard wood. Unbelievable service life in hard wood. TCT (main cutting edge), changeable crest of thread HSS. 1750 - 3000 rpm e.g. Ø 18 mm 2250 rpm in European hard wood.