"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.
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.