S-98164A431 4-40 x 7/16" ASME B18.3 Stainless Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with 316 stainless steel construction and passivated finish, ideal for harsh chemical and marine environments.
• Superior thread reliability with Class 3A fit and UNC coarse spacing, ensuring precise, vibration-resistant connections in industrial assemblies.
• High mechanical strength offering 70,000 psi tensile strength and Rockwell B55 hardness for durable, long-lasting fastening under stress.
• Efficient installation and removal via the 1/16" hex drive, providing secure tool engagement and reducing assembly time.
• Full threading coverage along the 7/16" length for maximum grip and uniform load distribution in various materials.
• Compliant with major industry standards including ASME B18.3, RoHS 3, and REACH, ensuring safety and regulatory adherence.
• Rounded button head design minimizes protrusion and damage risks, suitable for applications where a low-profile finish is critical.

Professional Applications & Engineering Value

Engineered for demanding sectors, this 4-40 UNC 316 stainless steel rounded head screw addresses common industrial challenges such as fastener failure in corrosive settings. The passivated finish enhances surface durability, while the coarse thread spacing and Class 3A fit provide excellent resistance to loosening under dynamic loads. Ideal for industrial machinery, marine equipment, and chemical processing systems, it ensures reliable performance where moisture, chemicals, or temperature variations are concerns. The combination of high tensile strength and fully threaded design supports secure fastening in metals and plastics, reducing maintenance needs and downtime.

Specification Summary & Compliance

This screw adheres to ASME B18.3 specifications, with precise Class 3A thread fit and UNC coarse spacing for consistent dimensional accuracy. It meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliance, ensuring environmental safety and regulatory alignment. The inch system measurements, including a 7/16" length and 0.112" thread diameter, support seamless integration in standard industrial applications.