"IMSCREWS 3/8 x 4-1/2 Heavy-Duty Lag Screws - 304 Stainless Steel (5 pcs)
Industrial-Grade Structural Penetration When projects demand the highest level of structural integrity, these 4.5-inch bolts deliver. The thick 3/8 diameter provides massive shear resistance, making these the professional choice for securing extra-thick timber beams, heavy-duty landscaping ties, or large structural brackets to 6x6 posts where deep anchoring is non-negotiable.
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 high-tension, 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 and maintains structural safety on high-value cedar, redwood, or premium structural framing.
FAQ ¡ñ Tools: Fits a standard 9/16 hex socket or wrench. ¡ñ Pre-drilling: Mandatory for this extreme length and diameter. Use a 1/4 bit for softwoods or 5/16 bit for hardwoods to prevent timber splitting. ¡ñ Why 4-1/2 length? Optimized for passing through 2.5 or 3 timber while maintaining a massive 1.5 + thread anchor in the base post.
ELITE CLAMPING POWER The engineered partial thread allows the shank to bypass the outer board, pulling thick timber together for a gap-free, rock-solid structural joint.
DEEP-CORE ANCHORING Optimized for penetrating multi-layer beams (up to 3 thick) and anchoring deeply into structural posts with oversized 3/8 diameter.
304 EXTERIOR SHIELD Forged from premium 304 (18-8) stainless steel to endure humid timber cores and prevent rust staining in cedar, redwood, or ACQ lumber.
MAX-TORQUE INTERFACE Robust hex head fits standard 9/16 socket drives, delivering maximum torque transfer for controlled installation in dense timber.
TECHNICAL SPECIFICATION To ensure safety and prevent splitting, pre-drilling a deep pilot hole (1/4 for softwoods, 9/32 for hardwoods) is required.