The steel thread cutting screw has a zinc plating, a Type F point style, and a serrated hex washer head. The type F point is suitable for heavy gauge sheet metal, aluminum, cast iron, brass, and plastic. The screw has machine screw threads that taper down to a blunt point with multiple cutting edges and chip cavities. Steel is often used in applications where strength is the primary consideration. The zinc plating offers corrosion resistance and has a reflective appearance. The hex washer head has six flat sides that a wrench can grip to turn from the side, enabling use when there is no space above the head for a screwdriver. The serrated flange acts like a washer to increase the fasteners bearing surface and distribute the clamping force over a larger area, providing a grip that resists loosening.
Thread cutting and thread rolling screws, two types of self-tapping screws, are threaded fasteners that create a mating thread in the wall of a hole. The two screws differ from each other in the way that they create the threads. Thread cutting screws cut the wall of the hole to create the thread, creating material chips that need to be cleared away from the hole to prevent clogging. Thread rolling screws, also called thread forming screws, do not remove material but instead press against the wall of the hole to displace the material and form the threads.