S-91247A553 1/4"-20 x 2 3/4" ASME B18.2.1, SAE J429 Medium-Strength Grade 5 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional Tensile Strength: With 120,000 psi tensile strength, this screw provides reliable performance in high-stress applications, reducing the risk of fastener failure.
• Superior Corrosion Resistance: Zinc plating offers a protective barrier against rust and environmental elements, extending the service life in demanding conditions.
• High Hardness for Durability: Rockwell C25 hardness ensures the screw maintains its structural integrity under heavy loads and repeated use.
• Secure Fastening with Coarse Threads: UNC coarse threads and Class 2A fit enable quick installation and strong holding power in various materials.
• Optimized for Heavy-Duty Use: Grade 5 classification and partial threading provide a balance of strength and flexibility for construction and industrial assemblies.
• Easy Installation and Removal: External hex drive design allows for straightforward application with standard tools, saving time on the job site.
• Compliance with Industry Standards: Meets ASME B18.2.1 and SAE J429 specifications, ensuring consistency and reliability in professional applications.

Professional Applications & Engineering Value

This Grade 5 hex head screw is engineered to address critical challenges in heavy-duty fastening, such as vibration resistance and long-term structural stability. Made from zinc plated steel, it combats corrosion in harsh environments, from outdoor construction to industrial machinery. The 1/4"-20 UNC coarse thread and partial threading enhance grip in materials like metal and wood, preventing loosening under dynamic loads. With a 2 3/4" length and external hex drive, it simplifies assembly in tight spaces, reducing labor time while maintaining 120,000 psi tensile strength for demanding applications like structural frameworks and equipment manufacturing.

Specification Summary & Compliance

This screw features precise Class 2A thread fit and adheres to UNC coarse thread standards for consistent performance. It complies with ASME B18.2.1 and SAE J429 Grade 5 manufacturing specifications, ensuring dimensional accuracy and reliability. Additionally, it meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, supporting safe and sustainable use in global markets.