S-97972A111 1/4"-20 x 1/2" Extreme-Strength Steel Flanged Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional durability with black-oxide steel construction, providing reliable corrosion resistance for extended service life in harsh environments.
• High tensile strength of 180,000 psi ensures secure fastening under heavy loads, reducing the risk of failure in demanding applications.
• Rockwell C38 hardness offers superior wear resistance, maintaining thread integrity and performance over repeated use.
• Flanged design eliminates the need for separate washers, simplifying installation and providing a larger bearing surface for enhanced stability.
• Class 2A thread fit with UNC coarse spacing allows for easy assembly and disassembly, minimizing cross-threading and improving efficiency in high-volume operations.
• External hex drive enables quick and secure tightening with standard tools, reducing installation time and labor costs.
• Fully threaded shank ensures consistent grip along the entire length, offering versatile fastening solutions for various material thicknesses.

Professional Applications & Engineering Value

This 1/4"-20 UNC hex head screw is engineered to address common industrial challenges, such as vibration loosening and material fatigue. The black-oxide steel material provides a protective layer that resists rust and oxidation, making it ideal for outdoor or humid conditions. With a coarse thread design and Class 2A fit, it ensures quick alignment and secure fastening in metals, plastics, and wood, reducing assembly errors. The flanged feature distributes clamping force evenly, preventing surface damage and enhancing joint integrity in machinery, automotive, and construction applications. Its high tensile strength and fully threaded body support heavy-duty use, offering reliable performance in structural assemblies and equipment maintenance.

Specification Summary & Compliance

This screw adheres to UNC thread standards with Class 2A tolerance for precise fit and interchangeability. It meets common industry specifications for dimensional accuracy, including thread size of 1/4"-20, length of 1/2", and flange diameter of 33/64". Manufactured in compliance with RoHS and REACH directives, it ensures environmental safety and is suitable for use in regulated sectors such as automotive and industrial equipment.