S-91771A106 4-40 x 1/4" ASME B18.6.3 Stainless Steel Phillips Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with passivated 18-8 stainless steel construction, ideal for harsh environments
• High tensile strength of 80,000 psi ensures reliable fastening under demanding mechanical loads
• Precision Class 2A thread fit provides consistent engagement and reduces cross-threading risks
• Standard 82° countersink angle allows for flush mounting in various applications
• Phillips No. 1 drive design offers efficient installation with common tools
• Full threading along 1/4" length maximizes grip strength and load distribution
• Compliance with ASME B18.6.3, RoHS 3, and REACH guarantees quality and environmental safety

Professional Applications & Engineering Value

These 4-40 UNC flat head screws deliver exceptional performance in industrial settings where corrosion resistance and mechanical reliability are critical. The passivated 18-8 stainless steel material prevents rust and degradation, making them suitable for outdoor equipment, marine hardware, and chemical processing applications. The coarse UNC thread and Class 2A fit ensure quick assembly and vibration resistance, while the flat head with 82° countersink provides a smooth, flush finish that eliminates protrusions. With 80,000 psi tensile strength and Rockwell B80 hardness, these screws maintain integrity under stress, reducing maintenance needs and downtime in industrial fastening systems.

Specification Summary & Compliance

This product features 4-40 UNC coarse threads with Class 2A thread fit for precise dimensional accuracy. It is manufactured in accordance with ASME B18.6.3 specifications and complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring adherence to environmental and safety standards.