S-93604A639 5/16"-18 x 3/4" ASTM A307, ASTM A153, ASME B18.5 Carriage Bolts

Key Features & Benefits at a Glance

• Superior corrosion resistance with hot-dipped galvanized steel coating, ideal for outdoor and high-moisture environments
• Enhanced load-bearing capacity with Grade 2 classification and 60,000 psi tensile strength for reliable structural connections
• Secure anti-rotation design featuring a square neck that locks into materials to prevent spinning during installation
• Wide rounded head profile distributes clamping force evenly and resists pull-through in wood and metal assemblies
• Optimized coarse UNC threading ensures faster installation and strong holding power in various materials
• Precision Class 2A thread fit guarantees consistent engagement and reduces cross-threading risks
• Full regulatory compliance with ASTM A307, ASME B18.5, RoHS 3, and REACH for trusted industrial use

Professional Applications & Engineering Value

This hot-dipped galvanized steel carriage bolt is engineered to address common industrial challenges like corrosion-induced failure and joint instability. The thick zinc coating provides a sacrificial barrier against rust, making it suitable for outdoor structures, agricultural equipment, and marine applications. The square neck design embeds securely into assembled materials, preventing rotation during torque application—a critical feature for wood-to-metal connections in framing, trailer manufacturing, and machinery guards. With full UNC coarse threading and 60,000 psi tensile strength, it maintains integrity under dynamic loads and vibration, while the rounded head offers a finished appearance and reduces snagging hazards in conveyor systems or public infrastructure projects.

Specification Summary & Compliance

This carriage bolt meets Class 2A thread tolerance for consistent fit and UNC coarse thread standards (5/16"-18). Manufacturing adheres to ASTM A307 for low-carbon steel bolts and ASME B18.5 for dimensional accuracy. It is certified RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliant, ensuring adherence to environmental and safety regulations. The bolt maintains a Rockwell B70 hardness and is fully traceable to specified material and performance benchmarks.