Hex Bolts-Hexagon Head Screw-8.8 Grade Alloy Steel-Black Oxide Finish

description

1.Robust Performance – Class 8.8 alloy-steel construction is through-hardened to ≥ 800 MPa ultimate tensile strength and ≥ 640 MPa yield strength. The matte black-oxide coating adds a light layer of corrosion protection, reduces glare and acts as a dry lubricant for consistent clamp load.

2. Broad Application Range – Widely used in household appliances, electronic products, communication products, automobiles, bicycles, furniture, ship assembly，machinery frames, heavy equipment, automotive chassis components, steel structures, jigs & fixtures, and general plant maintenance—any indoor or shielded outdoor environment where high strength is required and heavy galvanic protection is unnecessary.

3. Easy to Install – Precision-rolled ISO metric coarse threads engage smoothly, while the hexagonal head fits all standard spanners and sockets for rapid, high-torque tightening. The black-oxide finish lowers thread friction, helping achieve repeatable torque-to-tension values and minimizing galling.

4. Assured Quality – Produced under ISO 9001 quality management and fully compliant with ISO 898-1 / DIN 933 (ISO 4017) dimensional standards. Each lot undergoes hardness, thread-gauge, and magnetic particle crack inspection, with 3.1 material certificates and full traceability provided on request.