S-94063A550 1/4"-20 x 2" ASME B18.6.3 Tamper-Resistant Drilled Spanner Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction and passivated finish for extended service life in harsh environments
• Exceptional mechanical strength offering 70,000 psi tensile strength and Rockwell B70 hardness for reliable performance under high stress
• Secure tamper-resistant fastening with drilled spanner drive design, preventing unauthorized removal in critical applications
• Precision thread engagement with Class 2A UNC coarse threads ensuring consistent, vibration-resistant connections
• Flush surface installation featuring standard 82° countersink angle for smooth, aerodynamic finishes in assembled products
• Full-length threading providing maximum grip and load distribution across the entire 2" fastener length
• Regulatory compliance assurance meeting ASME B18.6.3 specifications while being RoHS 3 and REACH compliant

Professional Applications & Engineering Value

Engineered for demanding industrial applications, these 18-8 stainless steel flat head spanner screws deliver critical performance advantages where corrosion resistance and security are paramount. The passivated finish enhances surface durability while maintaining the material's inherent corrosion resistance, making these fasteners ideal for marine equipment, food processing machinery, and outdoor industrial installations. The drilled spanner drive configuration addresses tampering concerns in public infrastructure, transportation systems, and security-sensitive assemblies. With UNC coarse threading and Class 2A thread fit, these screws provide rapid installation and reliable performance in vibration-prone environments, while the 82° countersink angle ensures proper seating in standard chamfered holes for flush surface applications.

Specification Summary & Compliance

This 1/4"-20 UNC threaded flat head screw maintains precise dimensional control with Class 2A thread fit tolerances and head diameter tolerance of -0.025" to 0.03". Manufactured in compliance with ASME B18.6.3 specifications, the fastener features a standard flat head profile with 0.477" head diameter and 0.153" head height. Regulatory compliance includes RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) requirements, ensuring environmental safety and material transparency for global industrial applications.