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IMSCREWS

IMSCREWS 3/8 x 3-1/2 Hex Head Lag Screws, 304 Stainless Steel 18-8, Partially Threaded, Pack of 2 - Heavy Duty Wood Screws

IMSCREWS 3/8 x 3-1/2 Hex Head Lag Screws, 304 Stainless Steel 18-8, Partially Threaded, Pack of 2 - Heavy Duty Wood Screws

Regular price $5.99
Regular price Sale price $5.99
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Product Specifications

Fastener Type
Lag Screws
Diameter / Thread Size
3/8
Material
304 Stainless Steel
Head Style
Hex Head
Application
Woodworking

Confirm every listed dimension and the intended application before ordering.

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"IMSCREWS 3/8 x 3-1/2 Heavy-Duty Lag Screws - 304 Stainless Steel (2 pcs)

Extreme Strength for Heavy Timber Joints
When 1/4 or 5/16 fasteners aren't enough for structural safety, these 3/8 diameter bolts deliver industrial-grade stability. Perfect for securing large deck ledgers, heavy gate posts, or structural brackets to 4x4 or 6x6 beams. The 3.5-inch length ensures deep-core anchoring for load-bearing wood members.

Vise-Like Clamping Power
Our partially threaded shank features a smooth upper section that allows the bolt to spin freely in the outer board. This draws the timber members together into a gap-free, rock-solid joint, eliminating the bridging effect common in long full-thread screws. Ideal for pulling heavy lumber into tight, professional alignment.

304 Stainless Exterior Defense
Forged from premium 18-8 (304) Stainless Steel for ultimate weather resistance. compatible with ACQ pressure-treated lumber, preventing structural decay and unsightly rust streaks on high-value cedar, redwood, or deck framing.

Technical FAQ
¡ñ Tools Required: Fits a standard 9/16 hex socket or wrench.
¡ñ Pre-drilling: Mandatory for this diameter. Use a 1/4 bit for softwoods or 9/32 bit for hardwoods to prevent splitting.
¡ñ Why 3.5 length? Optimized for passing through 1.5 or 2 timber with a strong 1.5 + thread anchor in the support post.
¡ñ Resilience: Rated for marine, coastal, and high-humidity environments.

Specifications:
- Size: 3/8 x 3-1/2
- Thread: Partially Threaded (Max Clamping)
- Material: 304 Stainless Steel (18-8)
- Drive: 9/16 Hex Head
- Qty: 2 pcs"

Key Features

  • Medium-Duty Structural Strength: The 3/8 diameter provides reliable shear resistance for various wood construction projects. At 3.5 inches long, these screws are ideal for attaching 2x lumber to structural posts or headers.
  • 304 Stainless Steel: Made from premium 18-8 (304) Stainless Steel, providing effective protection against rust and corrosion. Compatible with ACQ pressure-treated lumber in outdoor or humid environments.
  • Partial Thread Clamping: The partially threaded shank allows the bolt to pull the outer board flush against the support structure, reducing gaps between surfaces for a more secure connection.
  • Outdoor Durability: These fasteners help maintain the appearance of premium wood like cedar and redwood by reducing the likelihood of rust streaks common with zinc-plated hardware.
  • Professional Installation: Use with a standard 9/16 hex socket. To prevent wood splitting, pre-drilling a pilot hole (recommended 1/4 for softwoods or 5/16 for hardwoods) is required.

Specifications

  • ASIN: B0F21B6R7B
  • Internal SKU: IMS0675
  • Size: 3/8" x 3-1/2"
  • Material: Stainless Steel
  • Finish: Stainless Steel
  • Head Style: Hex
  • Package Quantity: 2
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  • Confirm the Fit

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  • Choose the Material

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  • Install Correctly

    Use the matching driver and pilot-hole guidance for a secure installation.

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