S-90585A073 1/2"-13 x 1 1/8" ASME B18.3 Stainless Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 Stainless Steel construction and passivated finish, ideal for harsh environments and extended service life.
• High-strength performance offering 70,000 psi tensile strength and Rockwell B55 hardness for reliable, heavy-duty load-bearing applications.
• Precision thread fit with Class 3A UNC coarse threads ensuring secure, vibration-resistant connections and easier assembly.
• Flush mounting capability featuring a standard 82° countersink angle and flat head design for a smooth, unobtrusive surface finish.
• Secure and efficient installation enabled by a 5/16" hex drive, providing excellent torque transfer and reducing the risk of stripping.
• Full threading along the 1 1/8" length for maximum grip and adjustability in a wide range of material thicknesses.
• Regulatory compliance and quality assurance meeting ASME B18.3 standards and being RoHS 3 & REACH compliant for safe, global industrial use.

Professional Applications & Engineering Value

Engineered for demanding industrial applications, these 1/2"-13 UNC flat head screws address critical challenges like corrosion, vibration loosening, and high-stress fatigue. The 316 Stainless Steel material, enhanced by a passivated finish, provides exceptional resistance to chemicals, saltwater, and extreme temperatures, making them ideal for marine, chemical processing, and outdoor infrastructure. The Class 3A thread fit and coarse UNC threading ensure a tight, reliable hold that withstands dynamic loads and reduces maintenance needs. With a 5/16" hex drive and 82° countersink, installation is quick and secure, minimizing assembly time while achieving a flush surface for safety and aesthetics in machinery, structural frames, and equipment panels.

Specification Summary & Compliance

This screw features a 1/2"-13 UNC thread with a Class 3A precision fit, ensuring high dimensional accuracy and interchangeability. Manufactured in compliance with ASME B18.3 specifications, it includes a standard 82° countersink angle and full threading along its 1 1/8" length. The product is confirmed to be RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, adhering to environmental and safety regulations for global industrial use.