S-90471A424 1/4"-20 x 2 1/2" ASME B18.6.3 Steel Phillips Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with zinc-plated steel construction for extended service life in demanding environments
• High tensile strength of 60,000 psi ensures reliable fastening under substantial mechanical loads
• Class 2A thread fit provides consistent assembly performance and reduces cross-threading risks
• 100° countersink angle enables flush mounting for cleaner, safer surface finishes
• Full threading along 2-1/2" length offers maximum grip range and adjustment flexibility
• Phillips No. 3 drive delivers efficient torque transfer with common industrial tools
• UNC coarse threading enables rapid installation and superior vibration resistance

Professional Applications & Engineering Value

Engineered for industrial applications requiring both structural integrity and regulatory compliance, these zinc-plated steel flat head screws solve critical fastening challenges. The combination of 60,000 psi tensile strength and Rockwell B70 hardness ensures reliable performance in heavy machinery, equipment assembly, and structural frameworks where vibration resistance is paramount. The 100° countersink angle and flat head profile create seamless surface transitions, eliminating protrusions that could compromise safety or interfere with moving components. With UNC coarse threads and full threading, these screws maintain holding power in wood, metal, and composite materials while resisting loosening under dynamic loads.

Specification Summary & Compliance

This 1/4"-20 x 2-1/2" flat head screw features Class 2A thread fit per UNC standards with right-hand threading and Phillips No. 3 drive. Manufactured to ASME B18.6.3 specifications with complete compliance to RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring both mechanical precision and regulatory adherence for global industrial applications.