Turning Holders Tools Designations For External Turning M C L N R 2 5 2 5 M 1 2 Type of Locking Insert Shape Type of Tool Rake Angle / Shank Height Tool Length 32 A 40 B 50 C 60 D 70 E 80 F 90 G 100 H 110 J Hand of Tool / Shank Width 125 K 140 L 150 M 160 N 170 P 180 Q 200 R 250 S 300 T 350 U / Edge Length 400 V450W 500 Y Special X Optional Code C021