S-91247A560 1/4"-20 x 4 1/2" ASME B18.2.1, SAE J429 Medium-Strength Grade 5 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with 120,000 psi tensile strength for reliable performance in demanding applications
• Superior corrosion resistance from zinc plating, extending service life in harsh industrial environments
• Precision thread engagement with Class 2A UNC coarse threads ensuring consistent, vibration-resistant connections
• Optimized torque transmission through external hex drive design for secure installation with standard tools
• Enhanced durability from Rockwell C25 hardness, maintaining structural integrity under repeated stress
• Regulatory compliance assurance meeting ASME B18.2.1, SAE J429, RoHS 3, and REACH standards
• Versatile partial threading allowing both secure clamping and adjustable positioning in assemblies

Professional Applications & Engineering Value

These Grade 5 hex head screws deliver critical engineering solutions for industrial applications where high tensile strength and corrosion resistance are paramount. The zinc plated steel construction provides essential protection against environmental degradation in construction, machinery assembly, and structural frameworks. The UNC coarse thread design ensures rapid installation and superior vibration resistance in heavy equipment, while the external hex drive enables high-torque application without stripping. With partial threading, these fasteners offer precise clamping force control in complex assemblies, making them ideal for applications requiring both secure fastening and adjustability. The combination of 120,000 psi tensile strength and Rockwell C25 hardness ensures reliable performance in dynamic load conditions, reducing maintenance frequency and downtime in industrial operations.

Specification Summary & Compliance

This 1/4"-20 x 4 1/2" hex head screw features precision Class 2A thread fit with UNC coarse threading and right-hand orientation. Manufactured to ASME B18.2.1 and SAE J429 Grade 5 specifications, the fastener demonstrates full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. The partially threaded design provides 3/4" minimum thread length with consistent dimensional accuracy throughout the 4 1/2" length, ensuring reliable performance in industrial fastening applications requiring standardized components.