S-93548A595 5/16"-18 x 3" ASTM A307, SAE J429, ASME B18.5 Carriage Bolts

Key Features & Benefits at a Glance

• Superior anti-rotation performance due to the integrated square neck design, which securely locks into materials to prevent spinning during installation and under vibration.
• Enhanced corrosion resistance provided by the zinc-plated steel finish, extending the bolt's service life in demanding industrial environments.
• High tensile strength of 60,000 PSI (Grade 2) ensures reliable load-bearing capacity and structural integrity for heavy-duty applications.
• Excellent material hardness (Rockwell B70) provides resistance to wear and deformation, maintaining fastener performance over time.
• Coarse UNC thread profile (5/16"-18) allows for quicker installation and is less prone to cross-threading and clogging in wood and soft materials.
• Fully threaded, right-hand design offers maximum grip length and versatility for a wide range of material thicknesses.
• Wide, rounded carriage head distributes clamping force effectively and provides a finished appearance while reducing surface damage.

Professional Applications & Engineering Value

This zinc-plated steel carriage bolt is engineered to solve critical fastening challenges in construction, agricultural machinery, and structural assemblies. The square neck is a key engineering feature that bites into the material, providing superior anti-rotation and eliminating the need for a separate locking washer or tool access on the head side. This is vital for applications where vibration is a concern. The combination of Grade 2 strength and coarse UNC threading makes it exceptionally suited for wood-to-wood and wood-to-metal connections, ensuring a secure, long-lasting hold that resists loosening. Its 60,000 PSI tensile strength and robust construction make it a reliable choice for heavy-duty framing, trailer beds, and industrial equipment where failure is not an option.

Specification Summary & Compliance

This carriage bolt features a 5/16"-18 UNC coarse thread with a Class 2A thread fit for consistent and reliable engagement. It is manufactured to meet stringent industry standards including ASTM A307 and SAE J429 for material and mechanical properties, and conforms to dimensional specifications per ASME B18.5. The product is also RoHS 3 (2015/863/EU) Compliant, ensuring it is free of hazardous substances for safe use in various markets.