S-91773A743 4-48 x 1/2" ASME B18.6.3 Stainless Steel Round Head Phillips Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 Stainless Steel construction and passivated finish, ideal for harsh environments and extended service life.
• Exceptional mechanical strength offering 100,000 psi tensile strength and Rockwell B100 hardness for reliable performance under high-stress conditions.
• Precise and secure fastening with a Class 2A thread fit and UNF fine thread profile, ensuring tight, vibration-resistant connections.
• Efficient installation and removal featuring a No. 1 Phillips drive and rounded head design for easy tool engagement and reduced cam-out.
• Full-threaded design maximizes grip and load distribution along the entire 1/2" length for enhanced joint integrity.
• Compliance with major industry standards including ASME B18.6.3, ensuring dimensional accuracy and interchangeability.
• Environmentally responsible manufacturing with RoHS 3 and REACH compliance, meeting global regulatory requirements.

Professional Applications & Engineering Value

This 4-48 UNF fine thread screw is engineered to address critical challenges in precision assembly and demanding industrial environments. The 18-8 Stainless Steel material, combined with a passivated finish, provides excellent resistance to oxidation and chemical exposure, making it suitable for applications in electronics, aerospace, marine hardware, and medical devices where corrosion resistance is paramount. The rounded head and Phillips drive facilitate quick, secure fastening without damaging surrounding materials, while the fine thread and Class 2A fit ensure minimal backlash and superior holding power in thin materials or finely-tapped holes. Its high tensile strength and full threading support robust, long-lasting connections that withstand vibration and dynamic loads, reducing maintenance needs and downtime in industrial screw applications.

Specification Summary & Compliance

This fastener adheres to ASME B18.6.3 specifications, ensuring precise dimensional control and thread geometry. The UNF fine thread is manufactured to a Class 2A tolerance for consistent fit and performance. It is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming the absence of restricted hazardous substances. The screw is fully threaded, with a length of 1/2", and meets all declared mechanical and material standards for reliable use in regulated industries.