The DIN 6921 standard specifies the requirements for hexagon flange bolts with a reduced shank. These bolts are commonly used in applications where a smooth and finished appearance is desired, as the flange eliminates the need for a separate washer. The reduced shank allows for a more secure fit in tight spaces, making them ideal for machinery and equipment assembly. DIN 6921 bolts are known for their high strength and durability, meeting the strict quality standards set by the Deutsches Institut für Normung (DIN).