S-90185A418 5/16"-18 x 1 3/4" ASME B18.5, SAE J429 Carriage Bolts

Key Features & Benefits at a Glance

• Superior anti-rotation security with a square neck design that locks into materials to prevent spinning during installation and under vibration
• Exceptional strength for demanding applications with Grade 5 classification and a high tensile strength of 120,000 psi
• Enhanced corrosion resistance provided by the zinc-plated steel construction, extending the bolt's service life in various environments
• Reliable and fast installation thanks to the fully threaded UNC coarse thread pattern and Class 3A thread fit for precise, secure engagement
• Wide bearing surface for reduced surface damage due to the rounded, wide-profile carriage head that distributes load effectively
• Consistent performance and interchangeability ensured by compliance with ASME B18.5 and SAE J429 standards
• Safe for regulated industries as it is RoHS 3 and REACH compliant, meeting strict environmental and safety standards

Professional Applications & Engineering Value

This Grade 5 zinc-plated steel carriage bolt is engineered to solve critical challenges in industrial applications where vibration loosening and material integrity are concerns. The square neck design bites into wood, metal, or other substrates, providing superior anti-rotation security that prevents the bolt from turning during torque application and under dynamic loads. Combined with a fully threaded UNC coarse thread and Class 3A thread fit, it ensures quick, reliable fastening with high precision, reducing assembly time and maintenance needs. The zinc-plated finish offers a protective barrier against corrosion, making it ideal for outdoor equipment, agricultural machinery, and structural frameworks. Its rounded head with a wide profile minimizes surface damage, while the high tensile strength and Rockwell C25 hardness guarantee durability in heavy-duty settings like construction and automotive assemblies.

Specification Summary & Compliance

This carriage bolt features a 5/16"-18 UNC coarse thread with a Class 3A thread fit for precise dimensional accuracy and reliable performance. It is manufactured in accordance with ASME B18.5 and SAE J429 standards, ensuring consistent quality and interchangeability. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, supporting safe and environmentally responsible use in global markets.