S-91185A249 4-40 x 3/4" Thumb Screws

Key Features & Benefits at a Glance

• Enhanced grip and comfort with knurled Acetal plastic head for secure manual operation without tools
• Superior corrosion resistance from 18-8 stainless steel construction, ideal for humid or chemical environments
• Precise thread engagement with Class 3A fit and UNC coarse threads ensuring reliable fastening in industrial assemblies
• Quick installation and adjustment thanks to the fully threaded design and right-hand thread direction
• Low-profile round head design minimizes protrusion in tight spaces while maintaining easy access
• Broad temperature compatibility with head operating from 32° to 180° F for varied application settings
• Environmental and safety compliance meeting RoHS 3 and REACH standards for responsible manufacturing

Professional Applications & Engineering Value

This 4-40 UNC thumb screw combines the strength of 18-8 stainless steel with the ergonomic benefits of an Acetal plastic knurled head, addressing common challenges in equipment maintenance and assembly. The low-profile round head and coarse thread design enable rapid hand-tightening in confined areas, reducing installation time and tool dependency. Fully threaded with a Class 3A thread fit, it delivers consistent clamping force in electronic enclosures, machinery panels, and prototyping fixtures. The knurled texture ensures a non-slip grip even with gloves, while the stainless steel body resists rust in industrial or outdoor settings, prolonging service life and minimizing downtime.

Specification Summary & Compliance

This thumb screw adheres to UNC thread standards with a 4-40 thread size and Class 3A thread fit for high precision. It features a fully threaded 3/4" length and right-hand thread direction. The product is manufactured in compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it meets environmental and safety requirements for industrial components.