IMSCREWS 5/16"-18 x 3" Heavy-Duty 304 Stainless Steel Carriage Bolts (5 PCS)

Substantial Strength for Heavy Structural Timber Connections
The IMSCREWS 5/16" x 3" carriage bolt is engineered for structural projects requiring significant shear resistance and a professional finish. With a robust 5/16-inch diameter and a precise 3-inch length, these bolts are the ideal choice for securing deck railings, fencing main-posts, and timber-to-timber connections. The full thread design ensures maximum versatility, providing a snug and secure connection across various material combinations. Built for durability, they offer the stability required for long-term use in demanding residential and DIY applications.

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, low-profile appearance that reduces snagging hazards, making them a safe choice for playground equipment, park benches, and home decks. The integrated square neck prevents the bolt from spinning during installation, allowing for easy, one-sided fastening with a single wrench from the nut side.

Specifications:
- Thread Size: 5/16"-18 Coarse (UNC); Length: 3" (Measured from Under Head)
- Material: 304 (18-8) Stainless Steel; Full Thread

Pro-Tips:
1. Use a 5/16" drill bit to ensure a snug, structural fit for the square neck.
2. Pair with stainless steel flat washers and hex nuts on the nut side to distribute structural load and protect wood fibers.

Key Features

• Heavy-Duty 3 Reach: Precision-engineered to penetrate thick timber, such as standard 4x4 posts (3.5 actual) when countersunk, or joining two 2x4 boards with thick metal brackets.
• Reinforced 5/16 Diameter: The robust 5/16-inch shank provides a 50% increase in cross-sectional strength over 1/4 bolts, ensuring superior shear resistance for load-bearing joints.
• Marine-Grade 304 Stainless: Crafted from premium 18-8 (304) stainless steel for maximum rust prevention. Highly recommended for ACQ pressure-treated lumber and humid environments.
• Safety-First Aesthetic Finish: The smooth, drive-free domed head eliminates sharp edges and snagging, making it the premier choice for playground swings, slides, and garden benches.
• Anti-Spin Square Neck: The precision square shoulder locks firmly into wood fibers, allowing for easy, one-handed tightening of the nut from the opposite side.

Specifications

• ASIN: B0F2F5G54Q
• Internal SKU: IMS0807
• Size: 5/16"-18 x 3"
• Material: Stainless Steel
• Finish: Stainless Steel
• Head Style: Round
• Package Quantity: 5