The grade 2 steel heavy hex nut has a zinc-plated finish and meets American Society of Mechanical Engineers ASME B18.2.2 specifications. The heavy hex nut is taller and wider than a standard hex nut for a stronger hold and better security. It has six flat sides that a wrench can grip to turn from the side, enabling use when there is no space above the nut. Grade 2 steel, composed of either low or medium carbon steel, is often used in applications where toughness is the primary consideration. The zinc plating offers corrosion resistance and has a reflective appearance.Nuts are internally threaded fasteners that are used with bolts and threaded rods and studs to connect components. Several different nut styles fit a variety of application and installation requirements. Some styles, such as hex nuts, acorn nuts, flange nuts, and coupling nuts, must be tightened with a tool. Others, such as eye nuts, thumb nuts, and wing nuts, can be tightened by hand. Some nuts have a self-locking mechanism, such as a nylon patch or distorted threads, that makes them suitable for applications with a high amount of vibration. Heavy hex nut is taller and wider than standard hex nut for a stronger hold and better security Grade 2 steel is often used in applications where toughness is the primary consideration Zinc plating resists corrosion and has a reflective appearance Meets ASME B18.2.2 specifications ASIN B009EF2BFO Manufacturer Small Parts Item model number FSC112HHNZ