A
Anonymous
Mar 17, 2026
Rating: 5/5
Reliable fastener
Ordered for automotive application. Fits perfectly and handles vibration well.
Description
These are high-strength hex socket cap screws designed for securing heavy-duty machinery and structural assemblies where maximum clamping force is required. Manufactured from Grade 12.9 alloy steel, these fasteners undergo heat treatment to achieve superior tensile strength and resistance to deformation under extreme load. The components feature a black oxide finish that provides corrosion protection and reduces surface glare during installation. Each bolt includes a cylindrical head with an internal hexagonal drive, allowing for torque application in confined spaces where external wrench access is limited. Ensure the mating threads are clean and properly aligned before tightening to maintain the integrity of the connection and prevent stripping of the drive recess.
Reviews
Attributes
| Brand | - |
| Category | Industrial Small Parts / Connectors and Fasteners |
| Origin | - |
| Material | Alloy Steel |
| Grade Class | 12.9 |
| Finish | Black Oxide |
| Head Style | Socket Head Cap |
| Drive Type | Hex Socket |
| Thread Type | Coarse Thread |
| Tensile Strength | 1220 MPa (Min) |
| Hardness | 39-44 HRC |
| Country of Origin | Imported |
| Package Quantity | 100 Pieces |
5 reviews
A
Anonymous
Feb 24, 2026
Rating: 5/5
Great quality steel
Black oxide coating is even. No stripping on the hex socket.
A
Anonymous
Feb 15, 2026
Rating: 5/5
Exactly as described
Need high tensile bolts for my project. These met all specifications.
A
Anonymous
Feb 14, 2026
Rating: 4/5
Good but shipping slow
Bolts are genuine 12.9 grade. Took a bit longer to arrive than expected.
A
Anonymous
Feb 09, 2026
Rating: 5/5
Perfect for machinery repair
Used these for rebuilding a hydraulic press. High strength held up under torque.
5 FAQ
Q: Are these metric or imperial?
A: These are metric threaded fasteners.
Q: Do you offer bulk pricing?
A: Yes, contact sales for orders over 1000 units.
Q: Is the black oxide corrosion resistant?
A: It offers mild corrosion resistance; use oil for harsh environments.
Q: Can I return unopened boxes?
A: Yes, returns accepted within 30 days if packaging is intact.
Q: What torque specification do you recommend?
A: Please refer to standard ISO torque charts for Grade 12.9 based on diameter.
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