Vimal Industrial Corporation is a trusted supplier of DIN 603 round head square neck bolts in Mumbai, offering a wide range of sizes, materials, and finishes to meet diverse industrial requirements. These precision fasteners are widely used in wood-to-metal and wood-to-wood connections across construction, furniture, and machinery industries. Designed strictly as per DIN 603 standards, each bolt features a smooth domed head and a square neck for reliable anti-rotation performance. At Vimal Industrial Corporation, we ensure timely delivery, competitive pricing, and consistent quality backed by a strong sourcing network across India.
DIN 603 round head square neck bolts; also referred to as DIN 603 Carriage Bolts, are standardized fasteners defined by the German Institute for Standardization. These bolts are engineered with a domed mushroom head and a square neck section positioned just beneath it. The square neck locks into the base material during tightening, preventing the bolt from rotating even when only one side of the joint is accessible. This makes them a practical and dependable choice for single-sided installation across a wide range of structural and assembly applications.
These stainless steel fasteners are widely used in woodworking, metal fabrication, furniture assembly, and railway components. The round domed head delivers a clean, finished appearance on the visible face, while the square neck ensures a firm grip and natural tamper resistance without requiring additional tooling on the bolt side. As experienced bolts and nuts suppliers in Mumbai, we stock DIN 603 bolts across standard sizes in mild steel, stainless steel, and galvanized finishes, giving you the right material grade for both indoor and outdoor environments.
With growing demand for high-strength and tamper-resistant fastening solutions, DIN 603 Mushroom Head Square Neck Bolts have become a staple in both industrial and structural applications. These bolts offer a flush, smooth finish with a round domed head on one side, while the square neck underneath keeps the bolt locked in place during tightening, no wrench needed on the bolt side. This makes them a reliable choice for wooden beams, metal frames, and railway fastenings where only one side of the joint is accessible during installation.
As an authorized APL Fasteners dealer and experienced bolts supplier in India, Vimal Industrial Corporation supplies a comprehensive range of DIN 603 Carriage Bolts sourced from reputable manufacturers. Every bolt we stock meets international dimensional standards, giving procurement teams and engineers the confidence that what they order is exactly what arrives, no grade substitutions, no tolerance variations.
We offer DIN 603 bolts in a wide range of metric sizes (M5 to M20), lengths, and material grades. These bolts conform to DIN 603 standards, ensuring uniform dimensions, high performance, and compatibility across applications. Below are the standard specifications we supply:
| Parameter | Specification |
|---|---|
| Standard | DIN 603 |
| Bolt Type | Round Head with Square Neck |
| Thread Type | Metric (Full/Partial Thread) |
| Sizes Available | M5, M6, M8, M10, M12, M16, M20 |
| Length Range | 10mm to 200mm (varies by diameter) |
| Material Options | Stainless Steel (A2, A4) |
| Grades | A2-70, A4-70 (SS) |
| Surface Finishes | Self-Color |
| Head Style | Domed / Mushroom Head |
| Neck Type | Square (anti-rotation feature) |
| Applications | Wood-to-Metal, Railways, Fencing, Furniture, Construction |
DIN 603 Carriage Bolts have earned their place across industries not just because of their anti-rotation design, but because they solve a real installation problem; secure, clean fastening where access is limited to one side. From structural timber work to precision furniture assembly, these mushroom head square neck bolts are trusted wherever both performance and finish matter.
Common application areas include:
Wood-to-Metal and Wood-to-Wood Connections
Widely used in timber framing, deck construction, and structural joinery where the square neck bites into wood to prevent spin during tightening without damaging the surface.
Furniture Assembly
A preferred choice in furniture manufacturing where the smooth round head stays visible on the finished face, delivering a clean look without exposed hardware.
Railway Infrastructure
Used to fasten wooden sleepers, platform components, and track fixtures where vibration resistance and consistent clamping force are non-negotiable.
Fencing and Gate Installations
The flush, protrusion-free head makes these stainless steel fasteners a natural fit for outdoor fencing where safety and appearance both matter.
Automotive and Trailer Manufacturing
Secures wooden flooring, body panels, and internal supports in trailers and commercial vehicle assemblies.
Construction and Civil Engineering Projects
Used in temporary formwork, scaffolding timber connections, and permanent load-bearing wooden structures across infrastructure projects.
General Engineering and Fabrication Work
Applied wherever single-side bolt installation is required and rotation during tightening must be mechanically prevented.
As established bolts and nuts suppliers in Mumbai, Vimal Industrial Corporation stocks DIN 603 round head square neck bolts across all standard sizes, material grades, and finishes, ready for immediate dispatch to OEM units, contractors, and distributors across India.
As a reliable supplier of industrial fasteners in Mumbai, Vimal Industrial Corporation ensures that every client receives DIN 603 bolts that genuinely meet international dimensional and performance standards, not just on paper, but in practice. Our sourcing network, technical knowledge, and supply consistency make us a dependable procurement partner for businesses across construction, fabrication, OEM manufacturing, and infrastructure development across India.
Here’s why customers choose us for their fastener needs:
Ready Stock Availability — We maintain a wide range of DIN 603 Carriage Bolt sizes, materials, and finishes in stock so your orders move without waiting on lead times or back-order delays.
Sourcing from Certified Manufacturers — Every bolt we supply is procured from manufacturers who comply with DIN standards and subject their products to dimensional and load performance testing.
Custom Sizing and Bulk Orders — Whether you need project-specific sizing or high-volume procurement, we support custom supply schedules built around your production or construction timeline.
Competitive Pricing — We offer transparent, market-aligned rates on stainless steel bolts and mild steel grades alike, with cost-effective structures for large-volume and repeat orders.
Pan India Delivery — Fast, reliable dispatch across Mumbai, Maharashtra, and all major industrial zones in India, reaching OEM units, fabrication shops, and project sites on schedule.
Responsive Support — From prompt quotations to technical clarification on grades and finishes, our team stays available through the full procurement cycle, not just at the point of sale.
Whether you are a contractor, OEM manufacturer, hardware distributor, or procurement manager, Vimal Industrial Corporation delivers a consistent supply of DIN 603 round head square neck bolts with complete traceability and quality documentation wherever required. When you need a fastener supplier in India that understands what reliable sourcing actually means, this is where you start.
| Parameter | M5 | M6 | M8 | M10 | M12 | M16 | M20 |
|---|---|---|---|---|---|---|---|
| Thread Pitch (P) | 0,8 | 1 | 1,25 | 1,5 | 1,75 | 2 | 2,5 |
| b (for ≤ 125mm length) | 16 | 18 | 22 | 26 | 30 | 38 | 46 |
| b (for 125 < l ≤ 200mm) | 22 | 24 | 28 | 32 | 36 | 44 | 52 |
| b (for > 200mm) | - | - | 41 | 45 | 49 | 57 | 65 |
| Head Diameter dk (max) | 13,55 | 16,55 | 20,65 | 24,65 | 30,65 | 38,8 | 46,8 |
| Head Diameter dk (min) | 12,45 | 15,45 | 19,35 | 23,35 | 29,35 | 37,2 | 45,2 |
| Square Neck Height (max) | 5 | 6 | 8 | 10 | 12 | 16 | 20 |
| Square Neck Width (mix) | 4,52 | 5,52 | 7,42 | 9,42 | 11,3 | 15,3 | 19,16 |
| Specification | Details |
|---|---|
| Material | Steel |
| General Requirements | According to DIN 267 Part 1 |
| Thread Tolerance | 8g |
| Thread Standard | DIN 13 Part 13 |
| Mechanical Properties Standard | DIN ISO 898 Part 1 |
| Product Grade | C (previously type g) |
| Dimensional Tolerance Standard | DIN ISO 4759 Part 1 |
| Surface Requirements |
DIN 267 Part 2 – Surface finish quality DIN 267 Part 9 – Galvanic surface protection DIN 267 Part 10 – Hot-dip galvanizing DIN 267 Part 19 – Surface defects acceptance |
| Acceptance Testing | According to DIN 267 Part 5 |
The smooth head is designed for both aesthetics and security. Since there is no slot or drive for a screwdriver on the head, the bolt fastener cannot be tampered with or unscrewed from the outside, making it a popular “security bolt.”
Yes, they can be used for metal if the receiving hole has a square punch to accommodate the neck. In India, these are frequently used in heavy-duty industrial racking and structural steel projects where a flush, snag-free finish is required.
Yes, but you must use stainless steel fasteners. The chemicals in pressure-treated wood can corrode standard steel or zinc coatings very quickly. Sourcing high-quality SS bolts from a trusted supplier like Vimal Industrial ensures long-term structural safety.
The hole diameter should match the bolt’s shank diameter exactly. If the hole is too large, the square neck won’t bite into the material, causing the bolt fastener to spin freely when you try to tighten the nut.
Look for clean threading and a well-defined square neck. Partnering with a reputable distributor like Vimal Industrial ensures that your carriage bolts meet international DIN 603 standards and come with the necessary material certifications.
