Indexable Thread Turning Tool Holder STVOL12-4B Cutting Direction Left Hand Shank Square Shank Width 3/4 in Shank Height 3/4 in Overall Length 4-1/2 in Insert Shape TNMC-432 Inscribed Circle 0.5 in Insert Thickness 0.187 in Width Offset 0.875 in Mounting Style Screw Lock Insert Screw GTS-2 Torx Wrench T-20