S-91268A321 3/8"-16 x 5" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 150,000 PSI ensures reliable performance in high-stress industrial applications, reducing the risk of fastener failure.
• Grade 8 steel construction with Rockwell C33 hardness provides superior durability and resistance to wear, extending service life in demanding environments.
• Partially threaded design with UNC coarse threads offers enhanced grip and vibration resistance, improving assembly stability and ease of installation.
• Class 2A thread fit guarantees precise dimensional accuracy and smooth mating with nuts, minimizing assembly time and rework.
• External hex drive and hex head allow for high-torque application with standard tools, facilitating quick and secure fastening in tight spaces.
• Compliance with ASME B18.2.1 and SAE J429 standards ensures consistent quality and interoperability, supporting engineering specifications and safety requirements.
• RoHS 3 and REACH environmental compliance demonstrates commitment to safety and sustainability, making these screws suitable for regulated industries.

Professional Applications & Engineering Value

Engineered for heavy-duty industrial applications, this Grade 8 hex head screw addresses critical challenges in machinery, construction, and automotive sectors where high tensile strength and vibration resistance are paramount. The steel material and Rockwell C33 hardness provide exceptional load-bearing capacity, reducing the risk of shear or fatigue under dynamic stresses. With a 3/8"-16 UNC coarse thread and partial threading, it ensures secure fastening in materials prone to loosening, while the external hex drive simplifies maintenance and disassembly. Ideal for structural assemblies, equipment frames, and high-torque connections, this fastener delivers reliable performance, minimizes downtime, and supports compliance with industry standards like ASME B18.2.1 and SAE J429.

Specification Summary & Compliance

This hex head screw features precise inch system dimensions, including a 5" length and Class 2A thread fit for accurate mating. It adheres to UNC coarse thread standards with a 3/8"-16 thread size and meets manufacturing specifications under ASME B18.2.1 and SAE J429. Additionally, it is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and suitability for global industrial use.