S-91770A539 1/4"-20 x 5/8" ASME B18.6.3 Stainless Steel Truss Head Phillips Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with passivated 18-8 stainless steel construction, ideal for harsh industrial environments
• Exceptional holding power from 70,000 psi tensile strength and Rockwell B70 hardness for reliable, long-term fastening
• Wide bearing surface of the rounded truss head distributes load effectively, reducing surface damage and improving stability
• Easy installation with Phillips No. 3 drive and coarse UNC threading, allowing for quick assembly in various materials
• Full-thread engagement ensures maximum grip and vibration resistance across the entire fastener length
• Precision manufacturing to Class 2A thread fit guarantees consistent performance and interchangeability
• Regulatory compliance with ASME B18.6.3, RoHS 3, and REACH standards for safe, quality-assured usage

Professional Applications & Engineering Value

Engineered for demanding industrial settings, these rounded truss head screws address common challenges like vibration loosening and material stress. The passivated 18-8 stainless steel offers excellent resistance to oxidation and chemicals, prolonging service life in outdoor or corrosive environments. The wide truss head design minimizes pull-through in softer materials, while the coarse UNC thread provides rapid installation and strong holding power in wood, plastic, and metal assemblies. Ideal for machinery, electrical enclosures, and structural frameworks, these screws deliver reliable fastening performance with reduced maintenance needs.

Specification Summary & Compliance

This screw features a 1/4"-20 UNC coarse thread with Class 2A fit for precise dimensional accuracy. It is manufactured in compliance with ASME B18.6.3 specifications and meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring safety and sustainability in industrial applications.