The 7 Best 4 Inch Lag Screws (2023 reviews)

We consider a 4 inch lag screw to be a worthy investment in the long run. We are here to help you choose the right one for your purposes from all the best available products in market today.

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Our Top Picks:

Best Overall: Buy: Makers Bolt 4 Inch Lag Screw READ REVIEW

Best With Thread: Buy: power pro 4 Inch Lag Screw READ REVIEW

Best For treated lumber: Buy: Jake sales 4 Inch Lag Screw READ REVIEW

Best For pressure treated Wood: Buy: Chenango supply 4 Inch Lag Screw READ REVIEW

Best With Shield: Buy: Eastlo 4 Inch Lag Screw READ REVIEW

Best With anchor: Buy: Hillman 4 Inch Lag Screw READ REVIEW

Best For metal: Buy: Binifimux 4 Inch Lag Screw READ REVIEW

Best Overall: Makers Bolt 4 Inch Lag Screw

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These metal wood screws are great for exterior household and industrial applications such as deck building or joining lumber. The Makers Bolt fasteners are of the highest commercial-grade quality with uniform threads and well-defined heads and points. The rich black color will enhance the final appearance of any project.

These stainless black screws are coated with black oxide proudly applied in the usa to military specifications, giving the screws a sleek look and added corrosion and abrasion resistance. The Durable oxide and dry wax coating provide enhanced protection against peeling, scratches, and corrosion.

• Good brand reputation
• Good investment for long term

Best With Thread: power pro 4 Inch Lag Screw

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The power pro 4 inch lag screw is capable of outshining several other screw featured in this list in overall features in its price range. Whether you want a tight joint or a looser connection, the Power Pro 47877 Lag Screws can make it happen with ease. These screws have great holding power. It comes with vinyl fasteners and also it is great with the supplied bit. It is perfect to bite into the original wood siding.

These are a much larger size than normal deck screws and you need to predrill to use properly. The heads are half inch wide. The screws look great on the decking. It is easy to install with an impact driver, and can be screwed in directly without pilot holes or splitting the wood. It can be used in a variety of different ways to achieve the perfect fit.

• Excellent exterior construction (not just decking-rated) screw
• Capable of smiting down any piece of lumber in their path
• Very tough screws easy to drive as they have the pressure drill point
• Include decks, stairs, playsets, and many other outdoor wood projects

Best For treated lumber: Jake sales 4 Inch Lag Screw

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These 3" truss screws are a must to keep in your cabinet. The Modified truss head screw (1/2" head diameter) has better compression that forces deep, wide, and sharp screw threads. It provides an excellent multipurpose fastener for professional operations and demanding industries.

These Exterior Coated Torx/Star Drive Heavy Duty Structural Lag Screws are suitable for treated lumber and ground contact. It provides twice the torque of phillips or square drive screw heads. The wide and sharp screw threads provide maximum holding power. It comes with a “knurl“, or multiple small protrusions at the top of the threads. These construction lag screws far exceed standard lag bolts in shear compression forces.

• Deep strong threads pull the boards together and keep them tight
• Hour corrosion resistance in both acq and salt spray conditions
• Square drive heads for fast and solid insertion
• Corrosion resistant exterior coated screws passed 1200 hour salt spray test without coating failures

Best For pressure treated Wood: Chenango supply 4 Inch Lag Screw

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Chenango Supply makes beautiful and great screw with classic and smartly choosen materials. It is used to join items to lumber or wood floors. It is used for boat trailer lag screws to hold wood guides. It can also be used in conjunction with lag shield anchors to secure to concrete. These are good for applications where they will be used outside. It is used to fasten a handrail to boat dock.

• Great corrosion resistance for outside applications
• Being stainless steel, no worries about rust
• New and hot release

Best With Shield: Eastlo 4 Inch Lag Screw

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Hex head lag screws are coarse thread screws requiring a pre-drilled hole with minimal clearance above the fastener to prevent splitting or snappins. It is made of 304 stainless steel (no coating outside) which is superior to regular steel and any zinc plated fasteners, providing good strength and corrosion resistance in bad environments. They're often combined with washer to evenly distribute the pressure of the head as well as preventing pull through.

It is ideal for easy and quick installation with a hex drive and can tighten with more torque than phillips head machine screws. It is used for securing wood in heavy duty applications like deck building that standard wood screws cannot support the load. It is ideal for masonry application, use the screw in conjunction with a lag shield.

• Common applications include retaining walls, deck frames, and outdoor play equipment
• Good investment for long term

Best With anchor: Hillman 4 Inch Lag Screw

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This zinc hex lag screw has coarse threads designed for pre. It is used for directly fastening into wood surfaces. It is manufactured to be extremely sturdy, lag screws are some of the toughest fasteners. These particular screws have a sharp point, similar to some to the Simpson screws. It is six-sided and ideal for easy driving and quick installation.

It is designed to embed into the wood, rather than relying on a nut to secure the connection. It is used to build a treated 24x18 deck. These are used with a lag shield, and lag screws can be used in masonry applications.

• Common applications include retaining walls, deck frames, and outdoor play equipment
• Hex drive for controlled traction with a socket or wrench
• Drilled holes to prevent splitting or snapping, and requires minimal clearance above the fastener
• Designed to attach objects to wood and anchor masonry

Best For metal: Binifimux 4 Inch Lag Screw

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These extremely strong fasteners are usually used to connect heavy wood or other heavy materials that are subjected to high loads. Compared with most ordinary screws, the size of the lag screw is very large. These are driven by a wrench and are mainly used for fastening to masonry or wooden frames. It comes with a storage box. These screws are different from ordinary wood screws, self-drilling screws or metal plate screws.

• New and hot release
• Lot of satisfied buyers