S-91783A128 5-40 x 1/2" ASME B18.6.3 Stainless Steel Round Head Slotted Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction and passivated finish, ideal for harsh industrial environments
• Exceptional mechanical strength with 100,000 psi tensile strength and Rockwell B100 hardness for reliable performance under heavy loads
• Precision thread engagement with Class 2A thread fit ensuring consistent installation and vibration resistance
• Broad compatibility with UNC coarse threading and right-hand direction for versatile application across industrial equipment
• Enhanced durability through fully threaded design and rounded head profile, reducing stress concentration points
• Regulatory compliance meeting ASME B18.6.3 standards plus RoHS 3 and REACH environmental regulations
• Easy installation with standard slotted drive design for straightforward assembly with common tools

Professional Applications & Engineering Value

These 5-40 UNC rounded head slotted screws deliver critical performance advantages in demanding industrial applications. The 18-8 stainless steel composition combined with passivated finish provides exceptional resistance to corrosion and chemical exposure, making them ideal for machinery, electrical enclosures, and outdoor equipment where environmental factors threaten fastener integrity. The coarse thread design ensures rapid installation and superior holding power in various materials, while the fully threaded configuration maximizes grip length and load distribution. With 100,000 psi tensile strength and Rockwell B100 hardness, these screws maintain structural integrity under vibration and thermal cycling, preventing loosening and failure in critical assemblies. The rounded head profile minimizes protrusion while the slotted drive accommodates standard installation tools, streamlining maintenance and repair operations across manufacturing and industrial maintenance sectors.

Specification Summary & Compliance

This 5-40 UNC screw features precise Class 2A thread fit tolerances with coarse thread spacing and right-hand thread direction. Manufacturing complies with ASME B18.6.3 specifications for dimensional accuracy and performance standards. Environmental compliance includes RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring safe use in restricted substance applications. The 1/2" length and fully threaded design maintain consistent mechanical properties throughout the fastener body.