S-91286A112 1/4"-20 x 1 1/8" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with 150,000 PSI tensile strength for reliable performance in high-stress applications
• Superior corrosion resistance through zinc-flake coating that provides long-lasting protection in harsh industrial environments
• Optimized thread engagement with UNC coarse threads and Class 2A fit ensuring secure fastening and vibration resistance
• Maximum torque transmission through the external hex drive design that prevents stripping during installation
• Enhanced durability with Rockwell C33 hardness maintaining structural integrity under repeated stress
• Full-threaded design offering consistent gripping strength along the entire 1-1/8" length for versatile fastening applications
• Industry-standard compliance meeting ASME B18.2.1 and SAE J429 specifications for guaranteed quality and interoperability

Professional Applications & Engineering Value

These Grade 8 hex head screws deliver critical engineering solutions for demanding industrial applications where failure is not an option. The combination of 150,000 PSI tensile strength and Rockwell C33 hardness makes them ideal for heavy machinery, structural assemblies, and equipment subjected to extreme vibration and dynamic loads. The zinc-flake coated finish provides superior corrosion protection compared to standard platings, significantly extending service life in challenging environments. The 1/4"-20 UNC coarse threads with Class 2A fit ensure rapid installation and secure fastening in both soft and hard materials, while the external hex drive design allows for high torque application without slippage. These fully threaded steel fasteners are engineered to maintain clamping force integrity in critical joints, reducing maintenance frequency and downtime in industrial operations.

Specification Summary & Compliance

Manufactured to precise dimensional standards with Class 2A thread fit tolerance ensuring consistent performance across applications. Complies with ASME B18.2.1 and SAE J429 specifications for Grade 8 fasteners. Meets environmental regulations including RoHS 3 (2015/863/EU) compliance and REACH (EC 1907/2006) standards for hazardous substance restrictions. The inch system measurement and UNC coarse thread profile adhere to industry-standard specifications for North American industrial applications.