M5/M6/M8 Grade 12.9 High Strength Hexagon Bolts Carbon Steel Black Half-tooth Hexagon Bolts Full-tooth Bolts

Our Grade 12.9 High Strength Carbon Steel Black Hexagon Bolts—available in both full-tooth and half-tooth designs—are professional industrial fasteners engineered for heavy-duty, high-stress applications that demand exceptional strength, durability, and reliability. Crafted from premium carbon steel and heat-treated to meet strict 12.9 grade standards, these hexagon bolts deliver superior tensile strength and shear resistance, making them ideal for securing heavy components, machinery parts, and structural elements in industrial and mechanical settings.

 

The black oxide finish not only enhances the bolts’ wear resistance but also provides reliable corrosion protection, ensuring long-lasting performance in indoor industrial environments, mechanical workshops, and heavy-duty equipment applications. Available in two tooth options to suit diverse fastening needs: full-tooth bolts offer maximum grip and stability for applications requiring strong holding power and resistance to vibration, while half-tooth bolts balance secure fastening with easier installation in thicker materials or tight spaces.

 

Featuring a standard hexagon head design, these bolts allow for easy, efficient tightening with standard hex wrenches, reducing slippage and ensuring precise installation—perfect for professional contractors, maintenance teams, and industrial engineers. Available in popular industrial sizes (M5, M6, M8), they cover a wide range of heavy-duty applications, including industrial machinery assembly, heavy-equipment maintenance, mechanical fabrication, metal structure fastening, and industrial hardware projects.

 

Designed for versatility and industrial-grade reliability, these 12.9 grade carbon steel black hexagon bolts are suitable for industrial projects, mechanical manufacturing, heavy-duty repairs, and wholesale orders. Every piece is precision-machined to ensure consistent thread quality, size accuracy, and strength, delivering a trusted fastening solution that stands up to the demands of heavy use and high-stress industrial environments—ideal for professionals seeking top-tier, high-strength fasteners.