Metric Sizes Class 12.9 DIN 7991 Thermal Black Oxide Flat Socket Head

Metric Sizes Class 12.9 DIN 7991 Thermal Black Oxide Flat Socket Head Cap Screw

Metric Sizes Class 12.9 DIN 7991 Thermal Black Oxide Flat Socket Head Cap Screws are high-performance, precision fasteners engineered for maximum strength and flush-mount applications. Manufactured to DIN 7991 standards, these flat head socket cap screws feature a countersunk head design combined with an internal hex drive, delivering superior torque control and a clean, low-profile finish in demanding mechanical assemblies.

Designed for heavy-duty industrial use, Class 12.9 alloy steel provides exceptional tensile strength and load capacity, making these fasteners ideal for critical structural and dynamic applications.

High-Strength Class 12.9 Alloy Steel Performance

Exceptional Tensile & Shear Strength

Class 12.9 metric fasteners are heat-treated alloy steel screws with a minimum tensile strength of approximately 1,220 MPa. This makes them significantly stronger than Class 8.8 or 10.9 fasteners, providing reliable clamping force in high-stress environments such as heavy machinery, tooling systems, and precision equipment.

DIN 7991 Countersunk Design

The 90° countersunk flat head allows the screw to sit flush with the material surface when installed in a properly machined countersink. This design reduces protrusions, improves safety, and maintains smooth surfaces in applications requiring tight tolerances.

Thermal Black Oxide Finish Benefits

Enhanced Surface Protection

Thermal black oxide provides mild corrosion resistance while maintaining dimensional accuracy. Unlike plated finishes, black oxide does not significantly alter thread tolerances, ensuring precise fitment in metric assemblies.

Reduced Glare & Professional Appearance

The deep black finish offers a sleek, uniform appearance while reducing light reflection—ideal for tooling, automotive components, robotics, and visible assemblies.

Available Metric Sizes & Applications

Common metric diameters range from M4, M5, M6, M8, M10, M12, and larger, with varying lengths to suit specific grip requirements.

Typical applications include:

• Industrial machinery

• Automotive and motorsports assemblies

• Tool and die manufacturing

• Automation systems

• Heavy equipment fabrication

Why Choose Class 12.9 DIN 7991 Screws?

When strength, precision, and flush mounting are critical, Metric Class 12.9 DIN 7991 Thermal Black Oxide Flat Socket Head Cap Screws deliver unmatched performance. Their high tensile rating, dimensional accuracy, and professional finish make them the preferred choice for engineers and manufacturers demanding durability and reliability.