The Hex Socket Head Cap Bolt Set is made of 12.9 grade carbon steel alloy which provides strength and is commonly used for superior mechanical properties. The set of hexagon socket head cap bolts is widely used in household and office appliances, communication equipment, ship assembly and other machinery industries. > The Socket Head Cap Screw Set is ideal for use in confined areas where you need Socket Head Cap Screws. The Socket Head Cap Screw Set cylindrical hexagon socket is the fastener component, industrial and construction fasteners. 17 common sizes and different quantities for you to choose from for general purpose.