S-98704A635 1/4"-20 x 1 3/8" Thumb Screws

Key Features & Benefits at a Glance

• Effortless hand-tightening with a knurled black Acetal plastic head for superior grip without tools, even in low-clearance applications.
• Exceptional corrosion resistance provided by 18-8 Stainless Steel construction, ensuring long-term reliability in demanding environments.
• Precise and secure fastening guaranteed by the Class 3A thread fit and UNC 1/4"-20 coarse thread, offering high vibration resistance.
• Durable performance in a wide temperature range with a head that operates reliably from 32° to 180° F.
• Versatile partial threading allows for adjustable clamping and secure positioning in a variety of assemblies.
• Compliance with major environmental regulations including RoHS 3 and REACH, making it suitable for global supply chains and sensitive applications.
• Optional tool engagement via the 3/16" hex drive, providing flexibility for final torque adjustments when needed.

Professional Applications & Engineering Value

This low-profile thumb screw is engineered to solve common assembly challenges where tool access is limited and frequent adjustments are necessary. The 18-8 Stainless Steel body provides excellent resistance to rust and corrosion, which is critical for equipment in medical, electronics, and marine environments. The black Acetal plastic head is not only lightweight and electrically insulating but also features a knurled texture for a non-slip grip, reducing operator fatigue. The partially threaded design with a Class 3A UNC thread ensures a precise fit and high strength, preventing loosening under vibration. This combination of corrosion-resistant materials and an ergonomic head design delivers reliable performance in prototyping, access panels, and consumer electronics where both durability and user interaction are key.

Specification Summary & Compliance

This thumb screw adheres to the UNC 1/4"-20 thread standard with a Class 3A thread fit for high precision. The manufacturing and material composition are fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring they are free of restricted hazardous substances. The product meets the specified dimensional tolerances for the low-profile round head and partial threading up to a minimum of 1 inch.