"IMSCREWS 1/4""-20 x 3-3/4"" 304 Stainless Steel Carriage Bolts (20 PCS)

Substantial Support for Deep Structural Timber Connections
The IMSCREWS 1/4"" x 3-3/4"" carriage bolt is engineered for projects requiring deep penetration and stable structural support. With a standard 1/4-inch diameter and an extended 3.75-inch length, these bolts are well-suited for high-load joints where stability is critical, such as through-bolting standard 4x4 posts 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: 3-3/4"" (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 3.75-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 3-3/4 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: B0F2F842DJ
• Internal SKU: IMS0761
• Size: 1/4"-20 x 3-3/4"
• Material: Stainless Steel
• Finish: Stainless Steel
• Head Style: Round
• Package Quantity: 20