S-90185A414 1/4"-20 x 3 1/2" ASME B18.5, SAE J429 Carriage Bolts

Key Features & Benefits at a Glance

• Superior tensile strength of 120,000 psi ensures reliable performance in demanding applications, reducing the risk of fastener failure.
• Exceptional durability with Rockwell C25 hardness and zinc-plated steel construction provides excellent corrosion resistance and long service life.
• Secure anti-rotation locking via the integrated square neck design prevents the bolt from spinning during installation and under vibration.
• Wide, rounded head profile offers a larger bearing surface for better load distribution and a finished appearance.
• Coarse UNC threading and Class 3A thread fit enable faster, easier assembly and a more secure, precise connection.
• Full threading along the entire 3 1/2" length provides maximum flexibility in grip range and clamping applications.
• Compliance with major industry standards including ASME B18.5 and SAE J429 ensures consistent quality and interchangeability.

Professional Applications & Engineering Value

This Grade 5 zinc-plated steel carriage bolt is engineered to address critical challenges in industrial fastening and construction applications. The square neck design is a key feature that locks securely into materials, preventing rotation during torque application and under dynamic loads, which is essential for structural integrity in machinery, trailers, and wood-to-metal connections. The zinc plating on the steel substrate provides a protective barrier against rust and corrosion, extending the bolt's lifespan in both indoor and moderately harsh environments. Combined with its 120,000 psi tensile strength and coarse UNC 1/4"-20 thread, this bolt delivers a robust, reliable fastening solution that resists loosening and maintains clamp force, making it a trusted component for heavy-duty assemblies.

Specification Summary & Compliance

This carriage bolt features a 1/4"-20 UNC coarse thread with a Class 3A thread fit for high precision. It is manufactured from zinc-plated steel and conforms to ASME B18.5 and SAE J429 specifications for Grade 5 fasteners. The product is also verified to be RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, ensuring it meets stringent environmental and safety regulations for industrial use.