S-91247A483 3/4"-16 x 4" ASME B18.2.1, SAE J429 Medium-Strength Grade 5 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Superior Tensile Strength: With a 120,000 psi tensile rating, this screw provides reliable holding power for demanding industrial applications, reducing the risk of fastener failure.
• Enhanced Corrosion Resistance: The zinc plating finish offers excellent protection against rust and environmental degradation, extending the service life of your assemblies.
• Precise Thread Engagement: The 3/4"-16 UNF fine thread and Class 2A thread fit ensure smooth installation and a secure, vibration-resistant connection.
• High-Strength Material Grade: As a Grade 5 steel fastener with a Rockwell C25 hardness, it delivers optimal durability and resistance to wear under heavy loads.
• Efficient Installation & Removal: The external hex drive and standard 1 1/8" head width allow for easy torque application with common tools, speeding up assembly and maintenance.
• Optimized Load Distribution: The partially threaded design with a 4" length concentrates threads where needed, improving clamp load and joint integrity.
• Regulatory Compliance & Reliability: Meets ASME B18.2.1 and SAE J429 specifications, ensuring consistent quality and performance in regulated environments.

Professional Applications & Engineering Value

This Grade 5 hex head screw is engineered to address critical challenges in heavy machinery, structural frameworks, and automotive assemblies where vibration resistance and high tensile loads are common. The zinc plated steel construction combats corrosion in harsh industrial settings, while the UNF fine threading provides superior clamping force and minimizes loosening under dynamic stress. Its external hex drive facilitates quick installation with standard wrenches, reducing labor time in production lines. Ideal for construction equipment, industrial platforms, and transportation systems, this fastener ensures long-term reliability by maintaining thread integrity and load-bearing capacity, even in high-cycle applications.

Specification Summary & Compliance

This screw adheres to Class 2A thread fit tolerances for consistent engagement and is manufactured per ASME B18.2.1 and SAE J429 standards. It is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety. Key dimensional attributes include a 3/4"-16 UNF thread size, 4" length, and partial threading over a minimum of 1 3/4", providing precise application-specific performance.