S-92949A812 4-40 x 1 1/8" ASME B18.3, ASTM F879 Stainless Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction and passivated finish, ensuring long-term reliability in harsh environments
• Exceptional mechanical strength with 70,000 psi tensile strength and Rockwell B55 hardness for reliable performance under high-stress conditions
• Precision thread engagement through Class 3A fit and UNC coarse threads, providing secure fastening with reduced cross-threading risk
• Optimized installation efficiency with hex drive design and fully threaded shank, enabling quick assembly and maximum thread contact
• Enhanced clearance and aesthetic appeal with rounded button head profile, ideal for applications requiring low-profile fasteners
• Industry-standard compliance meeting ASME B18.3 specifications, ensuring interchangeability and quality assurance
• Environmental regulation adherence with RoHS 3 and REACH compliance for global market acceptance

Professional Applications & Engineering Value

These 4-40 UNC rounded head screws deliver critical engineering solutions where corrosion resistance and mechanical integrity are paramount. The 18-8 stainless steel composition, enhanced by passivated finish, provides exceptional protection against oxidation and chemical exposure in manufacturing, marine, and food processing equipment. The hex drive configuration ensures high torque transmission without cam-out, while the Class 3A thread fit maintains precise tolerances for vibration-resistant assemblies. The fully threaded design offers maximum grip length for sheet metal, machinery components, and electronic enclosures where uniform clamping force distribution is essential. These industrial screws solve common fastening challenges by combining corrosion resistance with high tensile strength, making them ideal for critical applications requiring both durability and precision threading performance.

Specification Summary & Compliance

Manufactured to exacting standards with Class 3A thread fit precision and UNC coarse thread specifications. These rounded head screws comply with ASME B18.3 dimensional requirements and maintain 1/16" hex drive compatibility. Environmental compliance includes RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring unrestricted use in global industrial markets. The inch system measurements guarantee dimensional consistency across North American manufacturing specifications.