S-95955A310 1/4"-20 x 1" Left-Hand-Thread Stainless Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 Stainless Steel construction, ideal for harsh environments and long-term reliability.
• Exceptional mechanical strength with 80,000 psi tensile strength and Rockwell B85 hardness for demanding, high-stress applications.
• Secure, non-reversing fastening provided by the left-hand thread direction, preventing loosening under counter-clockwise motion.
• Efficient installation and removal via the 5/32" hex drive, offering a firm grip and reducing tool slippage.
• Reliable thread engagement with UNC coarse thread spacing and Class 2A fit, ensuring consistent performance and ease of assembly.
• Full-length threading for maximum grip and load distribution along the entire 1" length of the screw.
• Compliance with strict environmental standards, being RoHS 3 and REACH compliant for safe, sustainable use in regulated industries.

Professional Applications & Engineering Value

This 1/4"-20 Left Hand UNC Rounded Head Screw is engineered to address critical challenges in industrial settings where standard right-hand threads may loosen under specific rotational forces. The left-hand thread direction is essential for applications involving counter-clockwise rotating machinery, providing a secure, non-reversing fastening solution that prevents accidental disassembly. Constructed from 18-8 Stainless Steel, it offers excellent corrosion resistance, making it suitable for use in moist, chemical, or outdoor environments without compromising integrity. The coarse UNC threading and Class 2A thread fit ensure quick, reliable installation and high vibration resistance, while the hex drive allows for high-torque application with common tools. Ideal for automotive, machinery, and heavy equipment assemblies, this screw enhances operational safety and longevity in demanding engineering applications.

Specification Summary & Compliance

This screw adheres to UNC thread standards with a Class 2A thread fit for precise dimensional accuracy and reliable performance. It is manufactured in compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it is free from hazardous substances and suitable for global industrial use. Key specifications include a thread size of 1/4"-20, coarse spacing, full threading, and a rounded button head style, all designed to meet rigorous engineering and environmental standards.