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IMSCREWS 1/4-20 x 3-1/4 Carriage Bolts, 304 Stainless Steel 18-8, Round Head & Square Neck, Full Thread, Pack of 10

Regular price $12.59 USD
Regular price Sale price $12.59 USD
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IMSCREWS 1/4"-20 x 3-1/4" 304 Stainless Steel Carriage Bolts (10 PCS)

Substantial Support for Deep Structural Timber Connections
The IMSCREWS 1/4" x 3-1/4" carriage bolt is engineered for projects requiring deep penetration and stable structural support. With a standard 1/4-inch diameter and an extended 3.25-inch length, these bolts are well-suited for high-load joints where stability is critical, such as through-bolting garden structures or joining multiple layers of dimensional lumber. Built for durability, they offer the stability necessary for long-term use in outdoor structures and residential DIY projects.

High Durability and Safety-Focused Design
Forged from premium 18-8 (304) stainless steel, these fasteners are highly resistant to rust and corrosion in coastal or humid environments. The smooth round head offers a clean appearance that reduces snagging hazards, making them an ideal choice for railings, play sets, and benches. The integrated square neck prevents rotation, allowing for easy, one-sided installation with a single wrench from the nut side.

Specifications:
- Thread: 1/4"-20 Coarse; Length: 3-1/4" (Under Head)
- Material: 304 (18-8) Stainless Steel; Full Thread

Pro-Tips:
1. Use a 1/4" drill bit to ensure a snug, structural fit for the square neck.
2. Pair with stainless steel flat washers on the nut side to distribute structural load and protect wood fibers.

Key Features

  • Self-Locking Square Neck: Features a precision-forged square neck beneath the head that bites into wood, preventing the bolt from spinning while the nut is tightened for a secure, one-sided install.
  • Full Thread Maximum Grip: The fully threaded 3.25-inch shank offers maximum grip and enhanced fastening power along its entire length, making it ideal for deep timber and structural DIY projects.
  • 304 Marine Grade Stainless: Forged from premium 18-8 (304) Stainless Steel for superior corrosion defense. Essential for outdoor structures, coastal decks, and ACQ pressure-treated lumber.
  • Extended Structural Strength: The 1/4 diameter provides reliable shear resistance. At 3-1/4 long, these bolts are Well-suited for through-bolting thick posts or connecting multiple layers of lumber.
  • Snag-Free Aesthetic Finish: The smooth, domed round head provides a professional, low-profile finish without sharp edges, ensuring safety for playground equipment, fencing, and furniture.

Specifications

  • ASIN: B0F2F4DWZ2
  • Internal SKU: IMS0754
  • Size: 1/4"-20 x 3-1/4"
  • Material: Stainless Steel
  • Finish: Stainless Steel
  • Head Style: Round
  • Package Quantity: 10
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