Bulk 5/16"-9 Hex Lag Screws Stainless Steel 316 (A4)

Marine-Grade, Corrosion-Resistant Fasteners for Reliable Wood Connections

Enhance your marine, chemical, and outdoor projects with our premium 5/16"-9 Hex Lag Screws, crafted from 316 (A4) stainless steel. These lag screws—often called lag bolts—have a 5/16" diameter and 9 TPI (threads per inch), delivering solid holding power in wood while offering superior corrosion resistance in challenging environments.

The hex head design makes installation straightforward with a wrench or impact driver, while coarse threads and a sharp point ensure maximum grip in wood. Remember to pre-drill pilot holes to prevent splitting and ensure proper alignment. These marine-grade screws are perfect for securing beams, constructing waterfront structures, or any project exposed to saltwater, chemicals, or moisture that demands top-tier durability.

Key Benefits of Our Stainless Steel 316 Hex Lag Screws

• Marine-Grade Corrosion Resistance: 316 (A4) stainless steel withstands saltwater, chemicals, and moisture better than standard steels.
• High Holding Power: The 5/16" diameter and 9 TPI coarse threads ensure stable, long-lasting wood connections.
• Reliable Strength: Suitable for moderate to heavy loads in harsh conditions.
• Easy Installation: Hex head allows driving with standard tools—just pre-drill your pilot hole first.
• Secure Connections: Once installed, these lag screws form semi-permanent bonds resistant to loosening.

Why Choose Our Bulk Lag Screws?

• Bulk Discounts: Ideal for marine professionals, contractors, and large-scale projects seeking volume savings.
• Wholesale Availability: Perfect for B2B customers needing substantial quantities over time.
• Premium Material: 316 (A4) stainless steel ensures top-tier corrosion resistance and long-term strength.
• Versatile Use: Suitable for marine construction, chemical processing, outdoor decking, fencing, and more.

Proper Pilot Holes and Installation Tips

Selecting the correct pilot hole size is crucial for preventing wood splitting and ensuring maximum holding power. For detailed guidance, refer to our Lag Bolt Pilot Hole Size Blog.

• Pre-Drilling: Follow recommended pilot hole sizes to protect the wood and simplify installation.
• Use Proper Tools: An impact driver or wrench works best. Avoid over-tightening to prevent head or thread damage.
• Ensure Correct Alignment: Drill pilot holes accurately and straight for optimal holding power and proper installation.

Product Specifications

• Diameter: 5/16"
• Thread Pitch: 9 TPI (Coarse Thread)
• Head Style: Hexagonal Head for easy driving
• Material: 316 (A4) Stainless Steel
• Standards Compliance: Meets common industry standards for lag screws

Ideal Applications

• Marine Construction: Ideal for docks, piers, and waterfront structures exposed to saltwater.
• Chemical Processing: Excellent for areas where chemical exposure demands top-tier corrosion resistance.
• Outdoor Projects: Decking, fencing, pergolas, and garden structures in harsh climates.
• Moderate to Heavy Loads: Suitable for tasks that need dependable, long-term wood connections.

Buy in Bulk and Build with Confidence

Choose our 5/16"-9 Hex Lag Screws in 316 (A4) stainless steel for secure, corrosion-resistant connections in demanding environments. With bulk and wholesale pricing, Monster Bolts provides top-quality marine-grade fasteners that stand the test of time. For advice on correct pilot hole sizes, don’t forget to explore our Lag Bolt Pilot Hole Size Blog.

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