Metric Carriage Bolts

South Coast Fasteners, Inc. supplies metric carriage bolts manufactured to DIN 603 standards for strength and reliability in structural and industrial applications. Carriage bolts are designed with a smooth, rounded head and square neck beneath, which locks into place when tightened, preventing the bolt from turning. This makes them ideal for wood-to-metal and wood-to-wood fastening where a flush, tamper-resistant surface is required.

South Coast Fasteners offers metric carriage bolts in multiple strength classes and stainless options, ensuring dependable fastening solutions across construction, infrastructure, and heavy equipment industries.

Get Superior-Quality Fasteners at Competitive Prices

Use the options below to find the fasteners you need in the quantities required for your application. Questions? Contact us today, and our team will gladly assist you in finding the best fastening solutions for your requirements. With South Coast Fasteners, you can count on helpful support, competitive pricing, and top-quality products for all your fastener requirements.

Types of Metric Carriage Bolts We Offer

Metric Class 4.6 Carriage Bolt, DIN 603, Zinc CR+3

These Class 4.6 carriage bolts provide reliable fastening strength for light- to medium-duty applications. The square neck prevents rotation while the rounded head ensures a clean, flush finish. Coated in zinc CR+3, they deliver corrosion protection and a bright appearance, making them suitable for construction, framing, and general-purpose use.

Metric Class 8.8 Carriage Bolt, DIN 603, Zinc CR+3

With higher tensile strength than Class 4.6, these Class 8.8 carriage bolts are designed for more demanding structural and mechanical applications. The zinc CR+3 finish offers corrosion resistance while maintaining a professional silver appearance. They are commonly used in heavy timber, equipment builds, and outdoor assemblies where strength and durability are required.

Metric Stainless A4 (316) Carriage Bolt, DIN 603

316 stainless carriage bolts provide the highest level of corrosion resistance, particularly in marine and chemical environments. Their smooth head and square neck design make them ideal for wood, composite, and metal connections that require both strength and resistance to rust. These bolts are frequently chosen for docks, outdoor structures, and chemical plant installations where long-term reliability is critical.

Material Options

South Coast Fasteners stocks metric carriage bolts in the following material grades, each designed for specific environments and performance needs.

Alloy Steel Class 4.6

Class 4.6 alloy steel provides dependable fastening for lighter-duty structural applications. It offers consistent strength for general-purpose construction and equipment use where extreme load capacity is not required. The material ensures secure fastening at an economical cost.

Alloy Steel Class 8.8

Class 8.8 alloy steel delivers higher tensile strength for demanding assemblies. These bolts are widely used in construction, equipment, and infrastructure projects where reliable fastening under stress is necessary. They balance strength and cost efficiency, making them a versatile choice across industries.

Stainless Steel A4 (316)

316 stainless steel provides maximum resistance to chlorides, saltwater, and aggressive chemicals. It is the best option for marine, chemical, and outdoor environments where fasteners face constant exposure to corrosion. This material ensures assemblies remain secure and rust-free over long service life.

Available Finishes

South Coast Fasteners offers metric carriage bolts in finishes that enhance durability and protect against corrosion.

Zinc CR+3

Zinc CR+3 delivers a bright silver finish with strong corrosion resistance. It is a common choice for construction, mechanical assemblies, and general-purpose fastening where appearance and protection matter. This finish provides a balance of durability and cost efficiency.

Why Choose South Coast Fasteners?

South Coast Fasteners is trusted for supplying bolts that meet strict standards for performance, strength, and consistency. With decades of experience and a dedication to quality, we provide customers with reliable products and expert guidance. Our inventory and service ensure industries from construction to marine always have the fastening solutions they need.

Order Metric Carriage Bolts Online Today

Order metric carriage bolts from South Coast Fasteners with confidence knowing that stock is always available. Our easy ordering system makes it simple to choose the correct grade, size, and finish. Whether for structural projects, marine construction, or equipment assembly, we deliver quickly with dependable support.