S-93604A643 5/16"-18 x 1 1/4" ASTM A307, ASTM A153, ASME B18.5 Carriage Bolts

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with hot-dipped galvanized steel coating for long-lasting performance in harsh industrial environments
• Secure anti-rotation locking through the integrated square neck design that prevents spinning during installation and use
• Reliable mechanical strength with Grade 2 classification, 60,000 PSI tensile strength, and Rockwell B70 hardness for demanding applications
• Optimized thread engagement with fully threaded UNC coarse design ensuring faster assembly and superior holding power
• Wide bearing surface from the rounded carriage head (0.719" diameter) distributing load evenly and reducing surface damage
• Industry-standard compatibility with Class 2A thread fit and right-hand threading for seamless integration with existing components
• Regulatory compliance assurance meeting multiple international standards for quality, safety, and environmental responsibility

Professional Applications & Engineering Value

These hot-dipped galvanized steel carriage bolts deliver critical engineering solutions where corrosion resistance and vibration resistance are paramount. The square neck design mechanically locks into materials during installation, eliminating rotation issues common in wood-to-metal and structural connections. With fully threaded UNC coarse threading, they provide maximum thread engagement in softer materials while maintaining 60,000 PSI tensile strength for structural integrity. The rounded carriage head offers a low-profile finish that won't snag while the hot-dipped galvanized coating creates a barrier against moisture, chemicals, and environmental exposure. Ideal for construction, agricultural equipment, trailer manufacturing, and outdoor structures where long-term reliability is non-negotiable.

Specification Summary & Compliance

This 5/16"-18 carriage bolt features precise Class 2A thread fit with UNC coarse threading (18 TPI) and right-hand direction. Manufactured to ASTM A307 specifications for low carbon steel bolts with ASME B18.5 dimensional compliance. The hot-dipped galvanized coating meets ASTM A153 requirements for corrosion protection. Fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring safe use across global markets.