S-91770A578 5/16"-18 x 1/2" ASME B18.6.3 Stainless Steel Truss Head Phillips Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance from passivated 18-8 stainless steel construction, ideal for harsh industrial environments
• Exceptional 70,000 psi tensile strength ensures reliable performance in heavy-duty applications
• Wide truss head design provides superior load distribution and prevents surface damage
• Class 2A thread fit with UNC coarse threading delivers secure fastening and easy installation
• Full threading along the entire 1/2" length maximizes grip strength and adjustment flexibility
• Rockwell B70 hardness rating guarantees long-term durability and resistance to wear
• No. 4 Phillips drive enables efficient installation with standard tools while reducing cam-out risk

Professional Applications & Engineering Value

These passivated 18-8 stainless steel rounded truss head screws solve critical industrial challenges where corrosion resistance and structural integrity are paramount. The wide truss head design distributes clamping force effectively, preventing material damage in sheet metal, electrical enclosures, and machinery assemblies. The UNC coarse thread pattern combined with Class 2A thread fit ensures rapid installation and vibration resistance in automotive, marine, and construction applications. The passivated surface treatment enhances the natural corrosion resistance of 18-8 stainless steel, making these Phillips drive screws ideal for outdoor equipment, food processing machinery, and chemical processing plants where moisture and corrosive elements are present.

Specification Summary & Compliance

Manufactured to precise ASME B18.6.3 specifications with Class 2A thread fit tolerance for consistent performance. Features 5/16"-18 UNC coarse threads on a 1/2" fully threaded shank with 0.313" thread diameter. Fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring safe use across global industrial markets.