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All-in-one Bulk 1/4"-20 Carriage Bolts A307 Grade A Coarse Hdg Upgraded Model [bogMHBzj]

$51.99 $166.99 -69%

All-in-one Bulk 1/4"-20 Carriage Bolts A307 Grade A Coarse Hdg Upgraded Model [bogMHBzj] Durable, Corrosion-Resistant Fasteners for Secure Connections in Outdoor and Industrial Settings Enhance your woodworking, construction, and outdoor projects with our premium 1/4"-20 Carriage Bolts

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All-in-one Bulk 1/4"-20 Carriage Bolts A307 Grade A Coarse Hdg Upgraded Model [bogMHBzj]

All-in-one Bulk 1/4"-20 Carriage Bolts A307 Grade A Coarse Hdg Upgraded Model [bogMHBzj]

Durable, Corrosion-Resistant Fasteners for Secure Connections in Outdoor and Industrial Settings

Enhance your woodworking, construction, and outdoor projects with our premium 1/4"-20 Carriage Bolts, crafted from A307 Grade A steel and Hot Dipped Galvanized (HDG) for improved corrosion resistance. These bolts provide dependable strength, making them ideal for a range of applications where durability is essential.

Carriage bolts feature a smooth, domed head with a square neck beneath. This design self-locks into a pre-drilled hole, preventing rotation as the nut is tightened. Perfect for wood-to-wood, wood-to-metal, and some metal-to-metal applications, carriage bolts are commonly used in fencing, decking, furniture assembly, and projects requiring tamper-resistant connections.

Undersized Options for HDG Fasteners

Some bolt lengths in this product line may be undersized to compensate for the zinc coating added during galvanizing. The zinc layer slightly increases the thread diameter, so starting with an undersized thread ensures that after galvanizing, the threads fit standard nuts and components properly. Refer to the variation details for which lengths are undersized.

  • Compensation for Zinc Buildup: Undersizing accounts for the added zinc thickness, ensuring a correct post-galvanizing fit.
  • Smooth Nut Installation: Undersized threads prevent overly tight fits after galvanizing, making nut installation easier.
  • Design Consideration: Specifying undersized HDG fasteners ensures proper functionality and ease of assembly in your project.

Key Benefits of Our HDG Carriage Bolts

  • Corrosion Resistance: Hot Dipped Galvanizing provides excellent protection against rust, pitting, and corrosion, ideal for outdoor and industrial environments.
  • Self-Locking Square Neck: The square neck design prevents the bolt from spinning as the nut is tightened, ensuring a secure and stable connection.
  • Flush, Clean Appearance: The domed head sits flush with the surface, offering a neat, professional look.
  • Easy Installation: Tap the bolt into place and tighten the nut—no twisting of the bolt head required.
  • Tamper-Resistant: The smooth head design means removal is only possible from the nut side, enhancing security.

Why Choose Our Bulk Carriage Bolts?

  • Bulk Pricing: Ideal for contractors and large-scale projects, save with volume discounts.
  • Wholesale Availability: Perfect for B2B customers needing substantial quantities.
  • High-Quality Material: A307 Grade A steel with HDG coating ensures robust durability and corrosion resistance.
  • Versatile Use: Suitable for woodworking, fencing, decking, furniture assembly, light construction, and more.

Product Specifications

  • Diameter: 1/4"
  • Thread Pitch: 20 TPI (Coarse Thread)
  • Length: Measured from under the head to the end of the shank
  • Head Style: Domed (Round) Head with Square Neck
  • Material: A307 Grade A Steel
  • Coating: Hot Dipped Galvanized (HDG) for enhanced corrosion resistance
  • Undersized Options: Certain lengths may be undersized (see variation details) to ensure proper fit post-galvanizing
  • Standards Compliance: Conforms to standard carriage bolt dimensions (ASME B18.5 or equivalent)

Ideal Applications

  • Woodworking Projects: Perfect for cabinetry, furniture, and wooden walkways.
  • Construction: Ideal for fencing, decking, and structural wood connections.
  • Outdoor Installations: Suitable for playground equipment, garden structures, and other exterior projects.
  • General Assembly: Great for DIY and professional builds needing dependable, tamper-resistant hardware.
  • Industrial Applications: Suitable for environments exposed to moisture and corrosive agents.

Complementary Products

  • Matching Nuts: (Add link to 1/4"-20 A307 Grade A HDG Nuts if available)
  • Matching Washers: (Add link to 1/4"-20 A307 Grade A HDG Washers if available)

Buy in Bulk and Build with Confidence

Choose our 1/4"-20 Carriage Bolts for secure, long-lasting connections in challenging environments. With bulk and wholesale pricing, Monster Bolts provides top-quality HDG fasteners—available in both standard and undersized thread options—to meet your project needs, backed by exceptional customer service.

✔️ Trusted by construction, industrial, and DIY professionals

✔️ Fast shipping and dependable support

What Our Customers Say

January 24, 2026

Absolutely no complaints!

It feels very robust and not at all flimsy.

- Jayden Watson.

January 24, 2026

Absolutely no complaints!

The build is sturdy and gives me confidence in its longevity.

- Melanie Powell.

January 24, 2026

Absolutely no complaints!

The aesthetic is very clean and modern.

- Stephen Wright.

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