S-91882A412 1/4"-20 x 5/16" Thumb Screws

Key Features & Benefits at a Glance

• Enhanced grip and torque application with a 1" diameter knurled head, reducing slippage during manual tightening in industrial environments.
• Superior corrosion resistance and durability thanks to the black-oxide steel finish, extending service life in demanding conditions.
• High tensile strength of 70,000 psi ensures reliable fastening under heavy loads, minimizing the risk of mechanical failure.
• Easy and quick installation with fully threaded UNC coarse spacing and Class 2A fit, providing smooth engagement and time savings.
• Robust material hardness (Rockwell B84) maintains thread integrity and resists wear over repeated use cycles.
• Compliance with RoHS 3 and REACH regulations guarantees safe, environmentally responsible use in global supply chains.
• Versatile right-hand thread design allows for standard tool-free operation in various assembly and maintenance tasks.

Professional Applications & Engineering Value

This 1/4"-20 thumb screw is engineered to address common challenges in industrial settings, such as the need for rapid, tool-free adjustments without compromising strength. The black-oxide steel construction offers excellent resistance to rust and abrasion, making it ideal for machinery, electronics enclosures, and automotive assemblies where exposure to oils and moisture is frequent. Its knurled head and raised profile provide a secure grip, even with gloved hands, reducing installation time and enhancing operator safety. The UNC coarse thread ensures quick engagement and high clamping force, while the fully threaded design distributes stress evenly, preventing loosening under vibration. This combination of features delivers reliable performance in industrial thumb screw applications, from prototyping to high-volume production lines.

Specification Summary & Compliance

This product adheres to precise dimensional standards, including UNC thread type with Class 2A thread fit for consistent compatibility. It meets RoHS 3 (2015/863/EU) compliance under exemption 6(a)-I for lead in steel and is REACH (EC 1907/2006) compliant, ensuring environmental and safety regulations are upheld. Specifications include a thread size of 1/4"-20, coarse spacing, right-hand direction, and full threading for uniform fastening performance.