ASME B18.3 – Hex Socket Screws Dimensions

DIN 912 is the industrial standard for hexagon socket head cap screws, also known as Allen bolts. These high-strength fasteners feature a cylindrical head with an internal hexagonal drive, allowing for high torque application in confined spaces where a traditional hex bolt would be inaccessible. While DIN 912 is the historical German standard, it has been functionally replaced by ISO 4762. Both standards are considered interchangeable for the vast majority of engineering applications.