S-90179A544 1/4"-20 x 1 1/4" Thumb Screws

Key Features & Benefits at a Glance

• Effortless hand-tightening and loosening with the spade-shaped thumb head, eliminating the need for tools in quick adjustments or assembly.
• Enhanced stability and load distribution from the integrated flange, preventing the screw from pulling through materials and increasing joint integrity.
• Superior durability and wear resistance due to the steel construction and Rockwell B55 hardness, ensuring a long service life in demanding environments.
• High mechanical strength with a 40,000 psi tensile strength, providing reliable performance under significant stress and vibration.
• Quick and easy installation with coarse UNC threading and Class 2A fit, enabling faster assembly and reducing the risk of cross-threading.
• Versatile fastening capability as it is fully threaded, allowing for a secure grip along the entire 1 1/4" length in various material thicknesses.
• Wide compatibility with standard 1/4"-20 UNC components, making it a practical choice for maintenance, repairs, and OEM applications.

Professional Applications & Engineering Value

This 1/4"-20 steel thumb screw is engineered to solve common industrial challenges where tool-free access and reliable fastening are critical. The spade head design offers an ergonomic grip for manual operation, ideal for applications requiring frequent adjustments, such as panel covers, access doors, and machinery guards. The inclusion of a flange distributes clamping force over a wider area, reducing surface damage and providing a more secure hold than standard screws. Made from robust steel with a Rockwell B55 hardness and 40,000 psi tensile strength, it withstands mechanical stress and resists deformation in harsh conditions. The UNC coarse thread and Class 2A fit ensure quick engagement and reliable performance in wood, metal, and plastic assemblies, making it a versatile choice for electronics, automotive, and industrial equipment.

Specification Summary & Compliance

This thumb screw adheres to UNC thread standards with a Class 2A fit for consistent dimensional accuracy and ease of assembly. Key specifications include a 1/4"-20 thread size, coarse spacing, right-hand direction, and fully threaded 1 1/4" length. The product is manufactured to meet general industry standards for quality and performance, ensuring reliability in various industrial fastener applications. It complies with common material safety guidelines, though specific certifications like RoHS or REACH should be verified based on the steel grade used.