Introducing our Carbon Steel Grade 12.9 High Strength Black Countersunk Square Neck Bolt — engineered for superior performance in demanding industrial and mechanical applications. Crafted from premium Grade 12.9 carbon steel, this bolt delivers exceptional tensile strength and durability, making it ideal for heavy-duty fastening where reliability is critical. The black finish provides enhanced corrosion resistance and a sleek, professional appearance. Featuring a precision-machined countersunk head and square neck design, it ensures secure, non-rotating installation while sitting flush with the mounting surface for a clean, streamlined look. Perfect for automotive, machinery, construction, and structural assemblies — this bolt combines rugged strength with precise engineering to meet the highest industry standards.