FOR FINISHING OPERATIONS on soft and hard wood, M.D.F., chipboard, plywood HW (integral tungsten carbide) execution. Especially recommended for all working where drilling is most important. Suitable for execution on plastic materials. POSITIVE HELIX: expulsion of the chip upward, excellent finishing of lower side of panel, also suitable for blind button hole execution; NEGATIVE HELIX: expulsion of the chip downward, excellent finishing of upper side of panel