Description

Key Features

Built for Framing

This Simpson Strong-Tie SDWS16400Q Strong-Drive SDWS Framing Screw is made for structural wood-to-wood fastening. It is code-listed for framing applications where you want stronger hold and better pull-out resistance than common nails.

Drives In Fast

The SawTooth Type-17 point starts quickly and reduces installation torque, so in most applications you can skip predrilling and keep moving through framing and remodeling work.

Cleaner Seating

A low profile washer head with underhead box nibs increases bearing surface and helps the screw countersink cleanly. That matters when you need tight structural connections without beating up the wood surface.

Overview

The Simpson Strong-Tie SDWS16400Q Strong-Drive SDWS Framing Screw is a 0.160 inch x 4 inch structural wood screw sold in a 750-count pack for wood-to-wood fastening. This is a structural wood screw designed for framing, remodeling, and engineered wood connections. Model Number: SDWS16400Q. If you need a fastener that installs with a driver instead of swinging a hammer, while giving better holding power than nails in many framing applications, this is the kind of screw you buy on purpose.

What makes this screw useful on the job is how it goes in. The SawTooth Type-17 point is built for fast starts and lower driving resistance, which helps eliminate predrilling in most applications. That saves time when you are running repetitive framing connections, fastening lumber, or tying members together in remodeling work. The serrated threads also help reduce installation torque, so the screw drives more efficiently and does not fight the tool as much on the way in.

The head design matters here too. Simpson uses a low profile washer head with underhead box nibs, which increases bearing surface in structural applications and helps the head seat cleanly into the wood. In plain terms, you get more clamp area than a small bugle head or typical deck screw head, which is exactly what you want when the fastener is doing real structural work. The T25 6-lobe drive also gives positive bit engagement, reducing cam-out and helping bits last longer during high-volume fastening.

For jobsite conditions, the Quik Guard coating is a big part of the value. It is intended for indoor and outdoor applications, so this framing screw works across general construction, exterior projects, and many everyday structural wood connections without stepping up to a more specialized stainless fastener. The carbon steel body provides the strength you expect from a structural screw, while the coating adds the corrosion protection needed for broader use than a basic interior-only fastener.

This specific SDWS16400Q version is the 4 inch length option with a 0.450 inch head diameter, 0.160 inch shank diameter, 8-1/2 threads per inch, and 2-1/2 inch thread length. Those numbers matter because they tell you this screw is sized for real framing and wood member tie-ins, not light trim work. The longer body gives you reach for thicker stock and stronger embedment, while the thread geometry is set up for wood-to-wood grab rather than metal fastening.

If you are a framer, remodeler, contractor, or serious DIYer working on structural wood assemblies, this is the right kind of fastener when you want speed, strong holding power, and easier installation with an impact driver or drill/driver. It is especially useful for wood framing, engineered wood applications, and indoor or outdoor projects where a code-listed framing screw makes more sense than a common nail or a generic construction screw.

Fast Starts in Framing Lumber

This screw is built to move through framing work without a lot of drama. The point geometry and serrated thread design help it start clean and drive with less effort, which matters when you are running a lot of fasteners in a day.

• SawTooth Type-17 point helps eliminate predrilling in most applications
• Serrated threads reduce installation torque for easier driving

Better Bit Engagement, Less Cam-Out

The T25 6-lobe drive is the kind of detail that saves frustration. It holds the bit better than a sloppy recess, so you spend less time dealing with stripped heads and worn-out bits when driving structural screws into dense lumber.

• T25 6-lobe drive for positive bit engagement
• Designed to help extend bit life during repeated installation

Structural Head Design That Seats Clean

Not all screw heads are created equal. The low profile washer head gives you the bearing surface needed for structural wood fastening, while the underhead box nibs help the head seat more cleanly into the material.

• 0.450 inch head diameter for increased bearing in structural applications
• Low profile head helps provide clean countersinking

Coated for Indoor and Outdoor Work

Quik Guard coating gives this framing screw more flexibility on the job. It is suited for indoor and outdoor use, which makes it a strong all-around option for contractors who do not want separate boxes of specialty screws for every routine wood connection.

• Quik Guard coating for indoor and outdoor applications
• Carbon steel construction for structural fastening strength

What’s in the Box

• (750) Simpson Strong-Tie SDWS Framing Screws with Quik Guard Coating

Key Specifications

Application	Fastening Wood-to-Wood
Material	Carbon Steel
Length (in.)	4 in.
Shank Diameter (in.)	0.160 in.
Head Diameter (in.)	0.450 in.
Drive Type	T25 6-Lobe
Head Type	Low Profile Head
Thread Type	Serrated Threads
Threads Per Inch	8-1/2 TPI
Thread Length (in.)	2-1/2 in.
Point Type	SawTooth Type-17 Point
Packaging Quantity	750

Compatibility

Driver Bit Interface

Uses a T25 6-lobe drive. Match it with a T25 bit for proper engagement and easier installation.

Material Compatibility

Designed for wood-to-wood and engineered wood applications. Not specified for metal, concrete, drywall, or masonry fastening.

Built For

Framing Construction Remodeling Woodworking General Contracting Engineered Wood Connections Indoor Projects Outdoor Projects

Pro Tip

Use a fresh T25 bit and keep steady forward pressure until the low profile head seats flush. That lets the 6-lobe drive do its job and helps you get the benefit of the SawTooth point without chewing up the recess.

Tool Nut’s Take

Tool Nut’s Take

Simpson Strong-Tie SDWS16400Q Strong-Drive SDWS Framing Screw Gets the Structural Stuff Done

This is the screw you grab when a regular wood screw is not enough and you want framing-friendly installation without giving up holding power.

• Who it’s for: Framers, remodelers, deck builders, and serious DIYers doing wood-to-wood structural fastening.
• Why it stands out: The SawTooth point, serrated threads, washer-style low profile head, and T25 6-lobe drive all work together to make installation faster and cleaner.
• Worth knowing: This is a 750-pack of 4 inch screws, so it makes the most sense for high-volume work or stocking the shop, not one small weekend repair.

Common Questions

• What is this screw designed for? It is designed for wood-to-wood fastening in framing, remodeling, and engineered wood applications.
• Do I need to predrill? Simpson states the SawTooth point eliminates the need for predrilling in most applications.
• What bit do I use? This screw uses a T25 6-lobe drive.
• Can it be used indoors and outdoors? Yes. The Quik Guard coating is intended to provide protection in indoor and outdoor applications.