S-91830A631 5/16"-18 x 1/2" Thumb Screws

Key Features & Benefits at a Glance

• Enhanced manual operation with knurled round head design providing superior grip and torque application without tools
• Exceptional corrosion resistance through 18-8 stainless steel construction for long-term reliability in harsh environments
• High-load capacity with 80,000 psi tensile strength and Rockwell B83 hardness for demanding industrial applications
• Quick installation through coarse UNC threads and Class 2A fit ensuring smooth engagement and time-saving assembly
• Full-threaded design maximizing engagement depth and providing consistent clamping force along entire length
• Raised head profile offering improved clearance and comfortable finger positioning during frequent adjustments
• Regulatory compliance meeting RoHS 3 and REACH standards for safe use in regulated industries and international markets

Professional Applications & Engineering Value

This heavy-duty thumb screw solves critical assembly challenges where frequent adjustments and tool-less operation are required. The 18-8 stainless steel construction provides excellent corrosion resistance for outdoor equipment, marine applications, and chemical processing environments where moisture and corrosive elements are present. The knurled round head with raised profile delivers exceptional grip even with greasy hands or when wearing gloves, reducing installation time and eliminating dropped fasteners. The 5/16"-18 UNC coarse threads with Class 2A fit ensure rapid engagement in metal, plastic, and composite materials, making these industrial thumb screws ideal for machinery guards, access panels, jigs, and fixtures requiring regular maintenance or quick disassembly. The combination of 80,000 psi tensile strength and full threading provides reliable performance in vibration-prone applications where secure fastening is critical.

Specification Summary & Compliance

This thumb screw features precision 5/16"-18 UNC coarse threads with Class 2A thread fit ensuring consistent engagement and dimensional accuracy. The fastener is manufactured from 18-8 stainless steel with full threading along the 1/2" length and right-hand thread direction. Compliance includes RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming environmental safety and restricted substance adherence for global industrial applications.