S-98930A134 M8 x 55 mm ISO 8678 Carriage Bolts

Key Features & Benefits at a Glance

• Superior corrosion resistance with zinc yellow-chromate plating for extended service life in harsh industrial environments
• Exceptional anti-rotation performance thanks to the integrated square neck design that prevents loosening under vibration
• High tensile strength rating of Class 8.8 with 110,000 psi capacity for demanding structural applications
• Optimized load distribution from the wide 18mm rounded head that prevents surface damage during tightening
• Reliable coarse threading with 1.25mm pitch for faster installation and reduced cross-threading risk
• Precision thread fit meeting Class 6g tolerance standards for consistent mating with nuts and threaded holes
• Partial threading design allowing unthreaded shank to bear shear loads while threaded portion provides clamping force

Professional Applications & Engineering Value

This M8 carriage bolt delivers exceptional engineering value through its zinc yellow-chromate plated steel construction and specialized square neck anti-rotation design. The combination addresses critical industrial challenges where vibration resistance and corrosion protection are paramount. The Class 8.8 strength rating ensures reliable performance in structural applications, while the partially threaded configuration provides optimal load distribution between the shank and threaded sections. The rounded head profile with 18mm diameter offers superior bearing surface, preventing pull-through in wood and metal assemblies. These features make it ideal for heavy-duty applications in construction, machinery, transportation equipment, and industrial frameworks where metric coarse threading and anti-rotation performance are essential for long-term reliability.

Specification Summary & Compliance

This carriage bolt maintains precise dimensional accuracy with Class 6g thread fit tolerance and complies with ISO 8678 specifications. The metric coarse threading features M8 x 1.25mm pitch with right-hand orientation and 22mm minimum thread length. Manufacturing adheres to international standards with Rockwell C22 hardness ensuring consistent mechanical properties. The product meets relevant industry regulations for heavy-duty fastening applications, providing assurance of quality and performance consistency across industrial implementations.