S-92949A132 5-40 x 5/16" ASME B18.3 Stainless Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction and passivated finish for long-lasting performance in harsh environments
• Exceptional mechanical strength delivering 70,000 psi tensile strength and Rockwell B55 hardness for reliable, heavy-duty applications
• Precision thread engagement with Class 3A fit and UNC coarse threads ensuring secure, vibration-resistant fastening
• Optimized installation efficiency through 5/64" hex drive design providing positive torque transmission and reduced tool slippage
• Enhanced surface compatibility with rounded button head profile minimizing surface damage and providing a finished appearance
• Full-threaded design offering maximum grip length and uniform stress distribution across the entire fastener
• Regulatory compliance assurance meeting ASME B18.3 specifications and environmental standards including RoHS 3 and REACH

Professional Applications & Engineering Value

These 5-40 UNC rounded head screws deliver critical engineering advantages in demanding industrial environments. The 18-8 stainless steel composition combined with passivated finish provides exceptional resistance to corrosion, oxidation, and chemical exposure, making them ideal for applications in manufacturing equipment, electronic enclosures, and marine components. The Class 3A thread fit ensures precise mating with corresponding nuts and tapped holes, eliminating play and maintaining joint integrity under vibration and dynamic loads. The hex drive design allows for high-torque installation without cam-out, while the rounded button head profile distributes clamping force evenly without marring contact surfaces. These fasteners solve common industrial challenges including thread stripping, corrosion-induced failure, and installation inefficiency, providing reliable performance in automated assembly systems, precision machinery, and critical structural applications where fastener integrity is paramount.

Specification Summary & Compliance

This 5-40 UNC screw features precision Class 3A thread fit with coarse thread spacing for optimal engagement in various materials. Manufacturing complies with ASME B18.3 specifications ensuring dimensional accuracy and performance reliability. The fastener meets stringent environmental regulations including RoHS 3 (2015/863/EU) compliance and REACH (EC 1907/2006) compliance, confirming the absence of restricted hazardous substances. Critical dimensions include 5/16" length, 0.238" head diameter, and 5/64" hex drive size, maintaining consistent quality across production batches for industrial applications requiring repeatable performance.