S-98164A528 5/16"-24 x 1/2" ASME B18.3, ASTM F879 Stainless Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 stainless steel construction and passivated finish, ideal for harsh industrial environments
• Precise thread engagement with Class 3A UNF fine threading ensuring reliable, vibration-resistant fastening
• High mechanical strength delivering 70,000 psi tensile strength and Rockwell B55 hardness for demanding applications
• Easy installation and removal with 3/16" hex drive and rounded button head design requiring minimal clearance
• Full thread coverage along the 1/2" length provides maximum grip and load distribution
• Regulatory compliance meeting ASME B18.3 standards and environmental regulations including RoHS 3 & REACH
• Consistent performance through standardized manufacturing ensuring dimensional accuracy and interchangeability

Professional Applications & Engineering Value

This 316 stainless steel rounded head screw with UNF fine threading and Class 3A fit addresses critical challenges in industrial assembly where corrosion resistance and thread precision are paramount. The combination of passivated finish and marine-grade 316 material provides exceptional protection against chemical exposure and atmospheric corrosion, making it ideal for marine equipment, chemical processing, and food manufacturing applications. The fine thread configuration offers superior resistance to vibrational loosening compared to coarse threads, while the hex drive and rounded button head design enable efficient installation in confined spaces. With full threading along its 1/2" length, this fastener ensures maximum engagement strength in thin materials and critical joints where reliability cannot be compromised.

Specification Summary & Compliance

This precision-engineered rounded head screw features 5/16"-24 UNF fine threads with Class 3A thread fit for superior dimensional accuracy and engagement. Manufacturing complies with ASME B18.3 specifications (ASTM F879) ensuring consistent quality and performance. The fastener is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, confirming its suitability for regulated industrial applications worldwide.