S-91744A538 1/4"-20 x 5/8" Thumb Screws

Key Features & Benefits at a Glance

• Superior manual grip and torque application with spade head design for easy hand-tightening without tools
• Enhanced stability and load distribution from the integrated flange, preventing loosening under vibration
• Excellent corrosion resistance in harsh environments due to 18-8 stainless steel construction
• Quick and reliable installation with UNC coarse threading and Class 2A fit for smooth engagement
• Full-threaded design ensures maximum holding power along the entire 5/8" length
• Right-hand thread direction provides standard, intuitive tightening for common industrial applications
• Compliance with environmental regulations including RoHS 3 and REACH for safe, sustainable use

Professional Applications & Engineering Value

This heavy-duty thumb screw is engineered to solve critical assembly challenges in industrial settings where frequent adjustments or tool-free access is required. The 18-8 stainless steel material provides reliable corrosion resistance, making it ideal for machinery, electronic enclosures, and outdoor equipment exposed to moisture or chemicals. The spade head offers an ergonomic grip for rapid manual operation, while the flanged design increases bearing surface area to reduce surface damage and maintain secure fastening under dynamic loads. With UNC coarse threads and Class 2A fit, it ensures quick alignment and robust performance in high-vibration environments, streamlining maintenance and reducing downtime.

Specification Summary & Compliance

This thumb screw features a 1/4"-20 UNC thread with coarse spacing and Class 2A thread fit for consistent dimensional accuracy and ease of assembly. It is fully threaded with a length of 5/8", head height of 19/32", and flange diameter of 0.435". The product complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental standards, ensuring it is free of restricted hazardous substances and suitable for regulated industrial applications.