Construction Lag Screw 15 x 6 with Torx Drive - Heavy Duty Box

In this review the focus is on a heavy duty construction lag screw sold in a full box of 400 pieces, aimed at contractors and serious DIYers who need durable fasteners for structural projects. The bottom line: this screw stands out for its exterior bronzed coating and a Type 17 notched extra sharp point that starts quickly and reduces walking, making it particularly useful when working with ACQ lumber or outdoor assemblies where corrosion resistance and ease of installation matter most.

Key Features

• Bronzed coated exterior: the finish prevents rust and corrosion so the fasteners hold up in outdoor conditions and around treated lumber.
• Type 17 notched point: the extra sharp point gives quicker starts and lowers the need for pre-drilling, saving time on repetitive tasks.
• T30 Torx drive compatibility: the Torx/Star drive accepts high torque without cam-out, improving installation speed for deck and fence work.
• Knurled screw shoulder: the shoulder reduces drill torque requirements, which helps when driving long runs of screws and minimizes strain on tools.
• High quality threads: threads cut clean and bite well into wood, delivering strong holding power for joists, posts, and beams.

Who It's For

This product is best suited for professionals and experienced DIYers who build decks, fences, roofing substructures, framing, timber frames, or post-and-beam work and need a reliable, corrosion-resistant fastener in bulk. The full box of 400 screws makes it practical for larger projects where consistency and value matter.

Those working exclusively indoors on finish carpentry or who require stainless steel for marine exposure should look elsewhere; this bronzed coated lag screw is formulated for general exterior use and treated lumber compatibility, not extreme saltwater environments.

Pros & Cons

Pros

• Excellent corrosion resistance from the bronzed exterior, suitable for ACQ lumber.
• Type 17 point and knurled shoulder reduce pre-drilling and torque, speeding installation.
• T30 Torx drive provides strong bit engagement and fewer stripped heads under high torque.
• Sold in a full box of 400, offering good value for large jobs.

Cons

• Not stainless steel, so it's a limited choice for harsh marine salt-spray applications.
• The head and shaft dimensions may require compatible hardware clearance planning on some trim details.

Specifications

Our Verdict

For contractors and serious DIYers needing a strong, corrosion-resistant lag screw in quantity, this box is a sensible choice because of the bronzed coating, Type 17 sharp point, and Torx drive that together reduce installation time and provide reliable holding power. It represents good value for exterior structural work, though those needing stainless performance for marine exposure should choose a different alloy.

Frequently Asked Questions

Are these compatible with treated lumber?
Yes, the bronzed coating is specified as ACQ lumber compatible, making them suitable for treated wood.

What driver bit is required?
A T30 Torx/Star bit is recommended to achieve full torque and minimize cam-out during installation.

Do these require pre-drilling?
The Type 17 notched extra sharp point reduces the need for pre-drilling in many situations, though very dense hardwoods may still benefit from pilot holes.