S-91185A851 5/16"-24 x 5/8" Thumb Screws

Key Features & Benefits at a Glance

• Effortless hand-tightening with a multi-lobe black acetal plastic head for superior grip and comfort, reducing tool dependency and assembly time.
• Exceptional corrosion resistance provided by 18-8 stainless steel construction, ensuring long-term reliability in various industrial environments.
• Precise and secure fastening with Class 3A fine UNF threading, offering a tighter fit and reduced risk of loosening under vibration.
• Durable plastic head performance with an operating temperature range of 32° to 180° F, suitable for many indoor and controlled applications.
• Full threading along the 5/8" length allows for adjustable positioning and maximum engagement in assemblies.
• Compliance with environmental standards including RoHS 3 and REACH, ensuring safe use in regulated markets and applications.
• Right-hand thread design for standard installation, facilitating intuitive use and reducing assembly errors.

Professional Applications & Engineering Value

This 5/16"-24 UNF thumb screw is engineered to address common assembly challenges in industrial settings, such as the need for quick, tool-free adjustments and reliable fastening without marring surfaces. The 18-8 stainless steel body offers excellent resistance to rust and corrosion, making it ideal for use in electronics, machinery, and outdoor equipment where moisture is a concern. The multi-lobe acetal plastic head provides a comfortable, non-slip grip that enables repeated hand-tightening and loosening, reducing operator fatigue and speeding up maintenance tasks. Its fine thread and Class 3A fit ensure minimal backlash and secure retention in pre-tapped holes, enhancing the integrity of assemblies subject to vibration. Fully threaded and compliant with RoHS 3 and REACH, this fastener supports efficient production lines and sustainable manufacturing practices.

Specification Summary & Compliance

This thumb screw adheres to UNF thread standards with a Class 3A thread fit for high precision in fine-thread applications. Key dimensions include a thread size of 5/16"-24, length of 5/8", and head diameter of 1 1/2". It is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it meets strict environmental and safety requirements for hazardous substances. The product is right-hand threaded and fully threaded for consistent performance.