S-93548A649 3/8"-16 x 6 1/2" ASTM A307, SAE J429, ASME B18.5 Carriage Bolts

Key Features & Benefits at a Glance

• Superior corrosion resistance with zinc-plated steel construction, extending service life in demanding environments
• Enhanced anti-rotation performance due to the integrated square neck design, preventing loosening under vibration
• High tensile strength of 60,000 psi ensures reliable load-bearing capacity for structural and heavy-duty applications
• Rockwell B70 hardness provides excellent durability and resistance to wear and deformation
• Coarse UNC threading with Class 2A fit allows for quick installation and secure fastening in various materials
• Partially threaded shank offers flexibility for applications requiring both clamped and unthreaded sections
• Compliance with major industry standards including ASTM A307, SAE J429, and ASME B18.5 guarantees consistent quality and interchangeability

Professional Applications & Engineering Value

This heavy-duty carriage bolt is engineered to address common industrial fastening challenges, such as joint failure due to rotation or corrosion. The zinc-plated steel material provides a protective barrier against rust, making it ideal for outdoor construction, automotive frames, and machinery exposed to harsh conditions. Its square neck design securely locks into wood or metal, eliminating the need for additional tools to prevent spinning during nut tightening. With a 3/8"-16 UNC coarse thread and Grade 2 strength, it ensures rapid assembly and reliable performance in structural connections, trailer builds, and industrial equipment where vibration resistance and long-term integrity are critical. The partial threading allows for precise grip length control, reducing stress concentrations and improving overall joint reliability.

Specification Summary & Compliance

This carriage bolt features precise Class 2A thread fit per UNC standards, ensuring consistent engagement and ease of assembly. It complies with ASTM A307, SAE J429, and ASME B18.5 manufacturing specifications, confirming dimensional accuracy and mechanical properties. Additionally, it is RoHS 3 (2015/863/EU) Compliant, meeting environmental regulations for restricted substances, making it suitable for global supply chains and eco-conscious projects.