S-90185A122 3/8"-16 x 1 3/4" ASME B18.5, SAE J429 Carriage Bolts

Key Features & Benefits at a Glance

• Superior anti-rotation performance thanks to the integrated square neck design, which securely locks into materials to prevent spinning during installation and under vibration.
• Exceptional strength for demanding applications with a tensile strength of 120,000 psi and a Grade 5 classification, ensuring reliable performance in heavy-duty and structural fastening.
• Enhanced durability and corrosion resistance provided by the black-oxide steel finish, offering protection against rust in various industrial environments.
• Optimized for quick and easy installation with a fully threaded, coarse UNC thread and right-hand direction, allowing for faster assembly and high clamping force.
• Consistent and reliable fit due to the Class 2A thread fit, which provides standard manufacturing tolerances for broad compatibility and ease of use.
• Wide head profile for superior load distribution with a 0.844" diameter rounded carriage head, helping to reduce surface damage and increase joint integrity.
• Guaranteed material hardness at Rockwell C25, ensuring the bolt maintains its shape and strength under high stress and wear conditions.

Professional Applications & Engineering Value

This Grade 5 Carriage Bolt is engineered to solve common industrial fastening challenges, such as joint loosening under dynamic loads and material degradation. The black-oxide steel construction provides a robust barrier against corrosion, extending service life in outdoor or humid settings like agricultural equipment, construction frameworks, and trailer assemblies. Its square neck is a critical feature that bites into the mounting surface, eliminating rotation during torque application—this is vital for applications where access to the bolt head is limited. Combined with fully threaded UNC coarse threading, it ensures rapid installation and high vibration resistance, making it a reliable choice for structural connections, machinery, and automotive applications that demand 120,000 psi tensile strength and consistent performance.

Specification Summary & Compliance

This bolt adheres to precise dimensional standards, including a Class 2A thread fit for consistent assembly and a 3/8"-16 UNC coarse thread specification. It is manufactured in compliance with ASME B18.5 and SAE J429 Grade 5 standards, ensuring mechanical properties and quality. Additionally, it meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulatory requirements, confirming it is free of hazardous substances and safe for use in various industrial and international markets.