1/4-20 x 1/2 Inch Coarse Zinc Plated Low Carbon Steel Type F Point Indented Hex Washer Head Thread Cutting ScrewThread cutting screws are self tapping screws that fill and secure existing holes in metal. They are easily removable and are often used as fasteners in items that need periodic maintenance. Thread cutting screws are most often used with wood and metal and do not generate the same stress as thread forming screws.