Wiper Lead Angle (e.g. "SEKN42 A FTN") Wiper Clearance Angle (e.g. "SEKN42A F TN") Cutting Edge Preparation (e.g. "SEKN42AF T N") Cutting Direction (e.g. "SEKN42AFT N ") - 8 - Code Letter Angle A 45° D 60° K 60° E 75° L 75° P 0° Code Letter Angle C 7° D 15° E 20° F 25-26° G 30° N 0° P 11° Code Letter Edge Preparation F sharp E honed T T-land S honed T-land X special chamfer Code Letter Direction R right-hand cutting only L left-hand cutting only N both right-hand and left-hand cutting