S-90409A188 5/8"-18 x 2 1/4" IFI 111, SAE J429 High-Strength Grade 8 Steel Flanged Hex Head Screws

Key Features & Benefits at a Glance

• Maximum Load-Bearing Capacity: With a tensile strength of 150,000 psi, this screw provides exceptional resistance to breaking under extreme tension, ensuring reliable performance in critical applications.
• Superior Durability & Wear Resistance: The Rockwell C32 hardness rating offers excellent resistance to deformation and wear, extending the fastener's service life in high-stress environments.
• Precise & Secure Fastening: The UNF fine thread with Class 2A fit ensures tighter, more vibration-resistant connections, reducing the risk of loosening in machinery and equipment.
• Enhanced Grip & Stability: The integrated flange distributes load over a wider surface area, minimizing surface damage and providing a more secure, stable hold without needing a separate washer.
• High-Strength Material Reliability: Made from Grade 8 steel, this screw is built for heavy-duty industrial use, offering consistent performance under demanding mechanical stresses.
• Efficient Installation & Removal: The external hex drive and hex head design allow for easy application of high torque with standard tools, speeding up assembly and maintenance.
• Regulatory Compliance & Safety: Meets IFI 111/SAE J429 standards and is RoHS 3 and REACH compliant, ensuring environmental safety and material quality for industrial procurement.

Professional Applications & Engineering Value

This Grade 8 hex head screw is engineered to address the demanding requirements of heavy machinery, construction, and automotive assembly, where failure is not an option. The combination of 150,000 psi tensile strength and Rockwell C32 hardness ensures it can withstand severe vibrational loads and high-stress conditions without shearing or deforming. The UNF fine threading with a Class 2A fit provides superior thread engagement and resistance to loosening, making it ideal for precision equipment and structural applications. The flanged design eliminates the need for additional washers, simplifying installation while distributing clamp load effectively to prevent surface damage. Fully threaded for maximum grip, this steel screw offers reliable, long-term fastening solutions in industries that prioritize safety and durability.

Specification Summary & Compliance

This fastener features a 5/8"-18 UNF thread size with Class 2A dimensional accuracy, ensuring precise fit and interchangeability. It is manufactured in compliance with IFI 111 SAE J429 standards, guaranteeing consistent quality and performance. The screw is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming it is free from hazardous substances and suitable for use in regulated industrial environments.