S-91746A113 4-40 x 5/16" Thumb Screws

Key Features & Benefits at a Glance

• Enhanced grip and torque application with a knurled round head design for easy manual tightening and loosening without tools
• Superior corrosion resistance and durability thanks to 18-8 stainless steel construction, ideal for harsh industrial environments
• High tensile strength of 80,000 PSI ensures reliable load-bearing capacity and resistance to deformation under stress
• Rockwell B85 hardness provides excellent wear resistance and maintains thread integrity over repeated use
• Precise Class 2A thread fit with 4-40 UNC coarse threads for quick assembly and secure fastening in various materials
• Fully threaded shank allows for maximum adjustability and consistent holding power along the entire 5/16" length
• Compliance with RoHS 3 and REACH standards ensures environmental safety and meets global regulatory requirements for industrial components

Professional Applications & Engineering Value

This 4-40 UNC thumb screw is engineered to address common challenges in industrial assembly, such as the need for quick access and tool-free adjustments. The 18-8 stainless steel material offers excellent resistance to rust and corrosion, making it suitable for applications in electronics, machinery, and outdoor equipment where exposure to moisture or chemicals is a concern. The knurled round head with a low-profile design ensures a secure grip, reducing slippage and improving operator efficiency in tight spaces. With a coarse thread and right-hand direction, it facilitates rapid installation and removal, minimizing downtime in production lines. Its fully threaded construction and high tensile strength provide consistent clamping force, preventing loosening from vibrations and enhancing the longevity of assembled components in demanding environments.

Specification Summary & Compliance

This thumb screw adheres to UNC thread standards with a Class 2A thread fit, ensuring precise dimensional accuracy and compatibility with standard nuts and tapped holes. Key specifications include a thread size of 4-40, a length of 5/16", and a coarse thread spacing for efficient engagement. It is manufactured to meet RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliance, confirming its safety for use in regulated industries without hazardous substances.