S-94239A101 1/4"-20 x 3/4" SAE J429 High-Strength Grade 8 Steel Serrated-Flange Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with 150,000 psi tensile strength and Grade 8 classification for reliable performance in high-stress applications.
• Superior corrosion resistance from zinc-plated steel construction, extending service life in harsh industrial environments.
• Enhanced vibration resistance through serrated locking flange design, preventing loosening under dynamic loads.
• Optimized installation efficiency with external hex drive and coarse UNC threading for quick assembly and reduced thread stripping risk.
• Consistent dimensional accuracy with Class 2A thread fit ensuring precise engagement and uniform clamping force.
• Robust mechanical durability backed by Rockwell C33 hardness for maintained fastener integrity under repeated use.
• Broad regulatory compliance meeting SAE J429, IFI 111, RoHS 3, and REACH standards for global supply chain compatibility.

Professional Applications & Engineering Value

Engineered for heavy-duty industrial applications, these Grade 8 hex head screws address critical challenges in machinery assembly, structural framing, and equipment manufacturing. The zinc-plated steel construction provides a sacrificial barrier against rust and chemical exposure, while the fully threaded UNC coarse spacing ensures rapid installation in thick materials and castings. The flanged design with serrations eliminates the need for separate washers and maintains clamp load under vibration, making these external hex drive screws ideal for automotive, construction, and agricultural equipment where high tensile strength and vibration resistance are paramount. Their right-hand threading and standardized dimensions facilitate seamless integration with existing industrial fastener systems.

Specification Summary & Compliance

Manufactured to Class 2A thread fit tolerances with UNC coarse thread specifications, these screws guarantee precise mating with standard nuts and tapped holes. Compliance with SAE J429 and IFI 111 standards ensures consistent mechanical properties and dimensional uniformity. Environmental regulations including RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) are fully met, confirming the absence of restricted substances for international industrial use.