DIN 931 refers to a specific standard established by the Deutsches Institut für Normung (DIN), which outlines the specifications for hexagon head bolts with a metric thread. This standard is crucial for ensuring the uniformity and reliability of bolts used in various engineering and construction applications. The DIN 931 standard details the dimensions, mechanical properties, and material requirements necessary for the production of these bolts, thereby facilitating compatibility and interchangeability in assembly processes. Adhering to this standard is essential for maintaining safety and performance in structural applications where these fasteners are employed.