S-91783A115 4-40 x 1" 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 for extended service life in harsh environments
• Exceptional mechanical strength with 100,000 psi tensile strength and Rockwell B100 hardness for heavy-duty applications
• Precision thread engagement with Class 2A fit and UNC coarse threads ensuring reliable fastening and vibration resistance
• Optimized installation efficiency through standard slotted drive design and fully threaded shank for consistent clamping force
• Regulatory compliance assurance meeting ASME B18.6.3 specifications and environmental standards (RoHS 3, REACH)
• Dimensional consistency with 1" length and 0.211" head diameter providing reliable interchangeability in assembly operations
• Right-hand thread direction with coarse spacing for quick assembly and disassembly in maintenance applications

Professional Applications & Engineering Value

These 4-40 UNC rounded head slotted screws deliver critical performance advantages in industrial settings where corrosion resistance and mechanical reliability are paramount. The 18-8 stainless steel composition, enhanced by passivated surface treatment, provides exceptional protection against chemical exposure and atmospheric corrosion in manufacturing equipment, marine components, and food processing machinery. The fully threaded design with Class 2A thread fit ensures maximum thread engagement across the entire fastener length, distributing load evenly and preventing loosening under vibration. The combination of 100,000 psi tensile strength and standardized rounded head profile makes these fasteners ideal for applications requiring both structural integrity and streamlined assembly processes in tight spaces.

Specification Summary & Compliance

Manufactured to exacting inch system dimensions with 1" length, 0.211" head diameter, and UNC coarse thread spacing. Thread specifications maintain Class 2A tolerance for precision fit. Compliant with ASME B18.6.3 mechanical standards, RoHS 3 (2015/863/EU) for hazardous substance restriction, and REACH (EC 1907/2006) regulations for chemical safety. Right-hand thread direction with fully threaded configuration.