S-91249A646 1/4"-20 x 4 1/2" ASME B18.6.3 Stainless Steel Pan Head Phillips Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with black-oxide coated 18-8 stainless steel, ideal for harsh environments and reducing maintenance costs.
• High tensile strength of 70,000 psi ensures reliable performance in heavy-duty and structural applications.
• Full threading along the 4 1/2" length provides maximum grip and uniform load distribution across the entire fastener.
• Phillips drive and UNC coarse threading enable quick, secure installation and reduced risk of cross-threading in various materials.
• Class 2A thread fit guarantees consistent, precise engagement with standard nuts and tapped holes for assembly efficiency.
• Compliance with ASME B18.6.3 ensures dimensional accuracy and interchangeability, meeting rigorous industrial standards.
• RoHS 3 and REACH compliance supports environmental safety and regulatory requirements in global markets.

Professional Applications & Engineering Value

This 1/4"-20 x 4 1/2" black-oxide 18-8 stainless steel screw is engineered to address common industrial challenges, such as corrosion in outdoor or chemically exposed settings. The black-oxide coating enhances durability by forming a protective layer that resists rust and wear, extending service life in applications like machinery assembly, construction frameworks, and automotive components. Its Phillips pan head design offers a low-profile, rounded head that minimizes protrusion while providing ample drive torque, reducing the risk of stripping during installation. Combined with UNC coarse threads, it ensures rapid, secure fastening in wood, metal, and plastic, making it a versatile choice for maintenance, manufacturing, and infrastructure projects where reliability and compliance with ASME B18.6.3 standards are critical for safety and performance.

Specification Summary & Compliance

This screw features precise Class 2A thread fit and adheres to UNC coarse threading standards for consistent performance. It meets ASME B18.6.3 specifications for dimensional accuracy and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and suitability for industrial use.