S-91783A552 1/4"-20 x 2 1/2" ASME B18.6.3 Stainless Steel Round Head Slotted Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance thanks to 18-8 stainless steel construction and passivated finish, ideal for harsh industrial environments
• High tensile strength of 100,000 psi ensures reliable, long-lasting fastening under demanding mechanical loads
• Excellent thread engagement with UNC coarse threading and Class 2A fit for quick assembly and vibration resistance
• Easy installation and removal with a standard slotted drive, compatible with common hand and power tools
• Optimized durability with Rockwell B100 hardness, maintaining structural integrity over repeated use
• Versatile partial threading allows for precise clamping force control in various machine and equipment applications
• Rounded head design provides a smooth, finished appearance while reducing risk of snagging or injury

Professional Applications & Engineering Value

This 1/4"-20 UNC coarse thread screw in 18-8 stainless steel is engineered to address common industrial challenges such as corrosion, vibration loosening, and high-stress fatigue. The passivated finish significantly enhances its resistance to oxidation and chemical exposure, making it suitable for industrial machinery, outdoor equipment, and applications in humid or corrosive settings. Its partially threaded design ensures secure fastening where unthreaded shank sections bear shear loads, while the rounded head with slotted drive facilitates straightforward installation in tight spaces. By combining material strength with precise ASME B18.6.3 compliance, this screw delivers consistent performance in machine assembly, automotive components, and structural frameworks, reducing maintenance needs and downtime.

Specification Summary & Compliance

This screw adheres to Class 2A thread fit for consistent dimensional accuracy and easy assembly. It meets ASME B18.6.3 specifications for dimensional and mechanical requirements, ensuring reliability in industrial applications. The product is fully RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, confirming it is free of hazardous substances and safe for use in regulated markets. With a 1/4"-20 UNC coarse thread, 2-1/2" length, and partial threading, it is manufactured to deliver precise performance and durability.