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IMSCREWS

IMSCREWS 5/16 x 5-1/2 Hex Head Lag Screws, 304 Stainless Steel, Partially Threaded Extra-Long Wood Bolts for Structural Framing, 20pcs

IMSCREWS 5/16 x 5-1/2 Hex Head Lag Screws, 304 Stainless Steel, Partially Threaded Extra-Long Wood Bolts for Structural Framing, 20pcs

Regular price $21.99
Regular price Sale price $21.99
Sale Sold out

Product Specifications

Fastener Type
Lag Screws
Diameter / Thread Size
5/16
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 5/16 x 5-1/2 Heavy-Duty Lag Screws - 304 Stainless Steel (20 pcs)

Extreme Structural Depth Pro-Pack
Our 5.5-inch lag bolts are built for the most substantial timber-to-timber connections. This 20-piece contractor pack provides industrial-grade shear strength, making it the professional choice for securing heavy 4x4 or 4x6 headers to structural 6x6 posts in pergolas, pavilions, and heavy-duty deck framing.

Vise-Like Clamping Power
Our partially threaded shank features a smooth upper section that allows the bolt to pull the outer timber tightly against the support structure. This creates a gap-free, rock-solid joint, eliminating the bridging effect common in extra-long full-thread screws for a professional-grade finish.

304 Stainless Weather Protection
Forged from premium 18-8 (304) stainless steel for elite rust protection in outdoor and humid environments. compatible with ACQ pressure-treated lumber. Prevents unsightly rust streaks on high-value cedar, redwood, or premium structural framing.

FAQ
¡ñ Tools: Fits a standard 1/2 hex socket or wrench.
¡ñ Pre-drilling: Mandatory for this extreme length. Use a 3/16 bit for softwoods or 7/32 bit for hardwoods to prevent timber splitting.
¡ñ Why 20 pcs? Best value for larger timber projects requiring multiple structural connections, such as full gazebo or pergola builds.

Specs:
- Size: 5/16 x 5-1/2
- Thread: Partially Threaded (Max Clamping)
- Material: 304 Stainless Steel
- Drive: 1/2 Hex Head
- Qty: 20 pcs"

Key Features

  • ULTIMATE STRUCTURAL CLAMPING The partial thread design allows the shank to bypass the outer beam, pulling thick timbers together for a gap-free, permanent structural bond.
  • DEEP-CORE ANCHORING The 5.5 reach is optimized for connecting 4x4 posts or multi-layer beams, providing elite withdrawal resistance and structural stability.
  • 304 MARINE-GRADE DEFENSE Forged from premium 304 (18-8) stainless steel to endure high humidity and prevent rust staining in cedar, redwood, or ACQ lumber.
  • STABLE TORQUE DELIVERY Robust hex head fits standard 1/2 socket drives, delivering maximum torque transfer for controlled installation in dense timber.
  • TECHNICAL SPECIFICATION To ensure structural safety and prevent splitting, pre-drilling a pilot hole (3/16 for softwoods, 7/32 for hardwoods) is mandatory.

Specifications

  • ASIN: B0F21GMH9K
  • Internal SKU: IMS0659
  • Size: 5/16" x 5-1/2"
  • Material: Stainless Steel
  • Finish: Stainless Steel
  • Head Style: Hex
  • Package Quantity: 20
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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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