Set Screws are often used for holding a pulley, gear, or other parts from turning relative to a shaft. Stainless steels are used for their corrosion resistance, high-temperature strength, scaling resistance, and low-temperature toughness. These properties account for their extremely wide use in practically every industry. Austenitic Stainless Steels are alloys of iron and carbon that contain between 16% and 30% Chromium, a maximum of 0.15% carbon, along with Nickel (or Manganese), and other alloying elements. The chromium, which helps develop a passive surface oxide film, provides corrosion resistance in stainless steels. Austenitic Stainless Steels are designated by a 3 digit SAE Stainless Steel Grade beginning with the number 3 (e.g. 304, 316). Another common naming convention for Austenitic Stainless Steels are 18/8, 18/10, 18/0, etc. where the 18 refers to the % of Chromium and 8 to % of Nickel contained in the material.Stainless Steel 18-8 denotes 18% chromium and 8% nickel. Stainless Steel 18-8 can be formed and welded. Stainless Steel 18-8 is typically non-magnetic, though the material can become slightly magnetic when cold worked (cold working refers to altering the physical properties of the material without the use of temperature).Hex socket drive systems are driven by hex wrenches or power tools with hexagonal bits. Vented fasteners have been drilled through their entire length to eliminate the possibility of virtual leaks caused by the trapped volume of air at the bottom of blind tapped holes. Cup Point is the most common point type, with good holding capability. A threaded fastener's size name includes information about the major external diameter, followed by the threads per inch, which indicates if it is coarse or fine. Fine threads are preferable when working with harder materials or when threading into a thin material. They are also stronger in tension than coarse threads, and generally provide higher shear strengths.