It is a tool that folds the tang after inserting the sprue.Press the tip against the tang and lightly hit the head with a hammer to easily break off at the notch.In addition, the snapped-off tang attaches to the magnet for confirmation on the spot.[Nominal M] 2, 2.2, 2.5, 2.6, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20[Nominal W] #2-56, #4-40, #5-40, #6-32, #8-32, 1/4, 5/16, 3/8, 7/16, 1/2, 9/16, 5/8, 3/4