Carriage Bolts – Round Head Square Neck Bolts for Secure & Aesthetic Fastening
Product Description
Carriage Bolts, also known as coach bolts, are distinguished by their domed, smooth round heads and a square neck directly beneath. This design prevents the bolt from turning when the nut is tightened, making them especially effective in wood and metal-to-wood assemblies.
At SM Fasteners, we manufacture premium-quality carriage bolts adhering to DIN 603 and ASME B18.5 standards. Our bolts are available in mild steel, high tensile steel (grades 4.6 & 8.8), and stainless steel (304 & 316) for enhanced corrosion resistance and long-term durability.
Applications
Carriage bolts are designed for aesthetics, security, and performance. Their tamper-proof design and smooth finish make them a preferred choice across various structural and aesthetic applications.
Used in:
Timber decking and furniture
Wooden fences and gates
Metal-to-wood structures
Playground and gym equipment
Trailer frames and automotive panels
Agricultural implements and railway sleepers
Technical Specifications
| Parameter | Details |
|---|---|
| Product Type | Carriage Bolts |
| Thread Type | Full / Partial Threaded |
| Head Style | Round Head with Square Neck |
| Standards | DIN 603, ASME B18.5 |
| Grades | 4.6, 8.8, Stainless Steel 304/316 |
| Material | Mild Steel, High Tensile Steel, Stainless Steel |
| Finish | Zinc Plated, Hot-Dip Galvanized, Black Oxide, SS Polished |
| Size Range | M6 to M20 / 1/4” to 1” |
Why Choose Our Carriage Bolts?
At SM Fasteners, we are committed to manufacturing fastening solutions that meet the highest standards of durability, precision, and aesthetic value.
✔️ Standard-Compliant Manufacturing (DIN 603, ASME B18.5)
✔️ Enhanced Anti-Rotation Design – Strong square neck hold
✔️ Superior Surface Finishes – For weather and rust protection
✔️ Available in Bulk or Custom Sizes – Ready stock & tailored production
✔️ Quality Assurance with Every Batch – Dimensional & material tests
✔️ Made in India – Export quality with competitive pricing
Packaging and Delivery
To ensure your carriage bolts reach you in perfect condition, we package them securely and offer flexible delivery options based on your volume and location.
Packaging Includes:
Clear polybags for retail
Corrugated boxes for bulk
HDPE/jute bags for large shipments
Wooden pallets with shrink wrap (export orders)
Custom “SM Fasteners” and “Made in India” branding
Industries We Serve
Our Carriage Bolts are used across a wide spectrum of industries, including:
Furniture and Interior Construction
Agricultural Equipment Manufacturing
Railway Infrastructure
Transport and Trailer Assembly
Playground and Recreational Equipment
Wooden Structure Construction
Automotive Coach Building
Documents Supplied
All products are shipped with complete traceability and documentation, including:
Material Test Certificate (MTC)
Product Conformance Certificate
Dimensional Inspection Report
Heat Number Stamping (on request)
Batch & Quantity Record Sheets
Country of Origin Declaration
Request a Quotation
Get custom pricing and technical support for your next project or bulk requirement.
📧 Email: susheel@smfastners.com
📞 Call: +91 8968469570
💬 WhatsApp Chat: Click to Chat
📦 Order now for assured quality, competitive pricing, and timely delivery – only from SM Fasteners.