Mandrel with 2-64 Screw LH (1/4" Shank) -For use on the left side of the lathe (clockwise rotation) -Note: Mandrel Body neck has a groove on it to identify it as left hand. Mandrel shank has a small groove on it to identify it as 2-64. Screw is blue in color to identify it as left hand and has a groove to identify it as 2-64.