The standard DIN 7991, also known as ISO 10642, specifies the characteristics of flat countersunk head screws. These screws are commonly used in various industries for applications where a smooth surface is required, such as in machinery, automotive, and construction. The flat countersunk head design allows the screw to sit flush with the surface, providing a clean and professional finish. DIN 7991 / ISO 10642 screws are available in different materials and sizes to suit different requirements and are known for their reliability and durability.