S-90185A550 1/4"-20 x 2" ASME B18.5, SAE J429 Carriage Bolts

Key Features & Benefits at a Glance

• Superior anti-rotation performance thanks to the integrated square neck that locks securely into materials, preventing spinning during installation and use.
• Enhanced corrosion resistance provided by the zinc-plated steel finish, extending the bolt's service life in various industrial environments.
• High tensile strength of 120,000 psi and Grade 5 classification ensure reliable performance under heavy loads and in demanding structural applications.
• Excellent durability with a Rockwell C25 hardness rating, offering resistance to wear and deformation over time.
• Wide, rounded head design distributes clamping force effectively, minimizing surface damage and providing a secure, finished appearance.
• Easy installation and removal with fully threaded UNC coarse spacing and right-hand thread direction, compatible with standard tools and common practices.
• Broad compatibility with Class 2A thread fit, ensuring consistent engagement with standard nuts and tapped holes.

Professional Applications & Engineering Value

This Grade 5 zinc-plated steel carriage bolt is engineered to solve critical challenges in industrial assembly, such as joint loosening due to vibration and material degradation from environmental exposure. The square neck design is a key feature that bites into wood or metal, providing superior anti-rotation without the need for additional locking washers, which streamlines installation and reduces component count. The UNC coarse thread ensures quick assembly and high resistance to cross-threading, making it ideal for time-sensitive projects in construction, agricultural machinery, and transportation equipment. With a 120,000 psi tensile strength and robust zinc plating, it withstands heavy dynamic loads and resists rust, ensuring long-term reliability in outdoor or high-moisture applications. This bolt delivers consistent performance where safety and durability are non-negotiable.

Specification Summary & Compliance

This carriage bolt adheres to precise dimensional standards, including a Class 2A thread fit for consistent assembly and UNC coarse threading (1/4"-20) per common industrial practices. It meets ASME B18.5 and SAE J429 specifications, ensuring uniformity and reliability in manufacturing. Compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) confirms it is free from hazardous substances, making it suitable for global supply chains and environmentally conscious applications.