"IMSCREWS 5/16 x 5-1/2 Heavy-Duty Lag Screws - 304 Stainless Steel (5 pcs)

Extreme Structural Depth for Large Timber
Our 5.5-inch lag bolts are built for the most substantial timber-to-timber connections. The 5/16 diameter provides industrial-grade shear strength, making these 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 5-1/2 length? Optimized for passing through 3.5 (4x) lumber with a massive 2 thread anchor in the base post.

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

Key Features

• ULTIMATE COMPRESSION Partial thread design allows the shank to bypass outer boards, pulling multi-layer timbers together for a professional, gap-free structural joint.
• DEEP-CORE ANCHORING The 5.5 reach is optimized for connecting thick beams to posts, providing massive withdrawal resistance and elite shear strength.
• 304 INDUSTRIAL SHIELD Forged from premium 304 (18-8) stainless steel to endure humid timber cores and prevent rust staining in cedar, redwood, or ACQ lumber.
• STABLE TORQUE DRIVE Robust hex head fits standard 1/2 socket drives, delivering maximum torque transfer for controlled seating in dense structural timbers.
• TECHNICAL SPECIFICATION To ensure safety and prevent splitting, pre-drilling a pilot hole (3/16 for softwoods, 1/4 for hardwoods) is mandatory.

Specifications

• ASIN: B0F21B16LC
• Internal SKU: IMS0657
• Size: 5/16" x 5-1/2"
• Material: Stainless Steel
• Finish: Stainless Steel
• Head Style: Hex
• Package Quantity: 5