DIN 6921
Class 10.9 non-serrated flange bolts (also called frame bolts) are high-strength metric fasteners featuring an integrated, smooth washer-like face under a hex head.
They provide an evenly distributed clamping load without scoring or damaging the mating surface, and match a high-tensile strength comparable to SAE Grade 8
Surface Protection: The smooth underside prevents scratching or gouging painted or soft metal surfaces.
Load Distribution: The wide flange spreads clamping force over a larger area than a standard bolt.
Applications: Widely used in automotive chassis, structural frame assemblies, and machinery where high tensile strength is needed but surface marring must be avoided.
