FandWay 720Pcs Bolts Nuts Set M3 M4 M5 M6 Button Head Screws 10.9 ISO 7380

Key Features

• High-Strength Material: Grade 10.9 high-carbon steel with hardness HRC 32-39 and tensile strength ≥1040 MPa. Black oxide coating provides a dense protective layer for long-term resistance to deformation and stripped threads.
• Button Head Design: Low-profile button head with hex socket for flush installation, smooth torque transmission, and minimized slippage.
• Versatile Sizes: Includes M3, M4, M5, M6 button head screws with matching 304 stainless steel nuts and flat washers. Comes with hex keys for turnkey assembly.
• Standards & Quality: Complies with ISO 7380 fastener standards; each screw undergoes hardness, thread and surface finish testing for precise sizing and secure threading.
• Portable Storage: Includes a compact storage case to organize screws and the hex key for easy transport and on-the-go repairs.

Note: For outdoor humid environments, consider 304 stainless steel variants to ensure corrosion resistance.