The Simpson Strong-Tie SDWS16312Q Strong-Drive SDWS Framing Screw is a 3-1/2 inch structural wood screw built for wood-to-wood fastening in framing, remodeling, and engineered wood applications. This is a framing screw designed for structural wood fastening. Model Number: SDWS16312Q. If you want a code-listed alternative to slower fastening methods for framing and general structural connections, this screw is built for that job.

What matters here is how the features work together during installation. The SawTooth Type-17 point helps the screw start fast and reduces installation torque, which means less resistance at the driver and less need to predrill in most applications. The serrated threads keep the screw moving efficiently through the wood, and the T25 6-lobe drive gives solid bit engagement so the driver stays planted instead of camming out under load.

The head design is just as important. Simpson uses a low-profile washer head with underhead box nibs, which gives you increased bearing surface in structural applications while still allowing clean countersinking. That makes this screw a good fit where you need the head to seat neatly without giving up clamping force. For framing, ledger-style wood connections, blocking, and general fastening wood-to-wood, that combination saves time and leaves a cleaner finished connection.

In terms of build, the SDWS16312Q uses a 0.160 inch shank diameter and a 0.450 inch head diameter with an 8-1/2 TPI thread pattern and 2 inch thread length. On the job, that translates into a structural fastener that is sized for serious wood fastening rather than light trim or finish work. It is designed to pull members together and hold them there, whether you are working with dimensional lumber or engineered wood components.

For real-world jobsite use, the Quik Guard coating is a big part of the appeal. It is intended for indoor and outdoor applications, and the product data also calls out use with treated lumber. That makes the screw more versatile for contractors and serious DIY users who move between indoor framing, exterior structures, and general-purpose wood construction without wanting separate fastener inventories for every task.

This specific package includes 750 screws, so it is clearly aimed at high-volume work rather than a one-off repair. Carpenters, framers, remodelers, deck builders, and general contractors are the obvious users. Serious DIY builders tackling sheds, pergolas, framing repairs, or other structural wood projects will also get the value here, especially if they want a fastener that installs cleanly with a T25 bit and is built for more than basic wood screw duty.

Simpson Strong-Tie SDWS16312Q Strong-Drive SDWS Framing Screw is a real workhorse framing fastener

If you need a structural wood screw that installs fast, seats clean, and holds like it should, this one earns its place in the truck.

• Who it's for: Framers, remodelers, deck and outdoor builders, and serious DIY users doing real wood-to-wood structural fastening.
• Why it stands out: The SawTooth point, low-profile washer head, and T25 6-lobe drive are a smart combination. It starts fast, resists bit slip, and gives solid bearing once seated.
• Worth knowing: This is a 750-pack, so it makes the most sense if you are burning through fasteners regularly. Also, make sure you have the right T25 bit on hand since it is not listed in the box contents.

• What is this screw used for? It is designed for fastening wood-to-wood and engineered-wood connections, including framing, remodeling, and indoor or outdoor projects.
• Does it require predrilling? The product data says the SawTooth point eliminates the need for predrilling in most applications.
• What bit does it use? It uses a T25 6-lobe drive, and the installation overview specifically says to use a T25 bit.
• Can it be used outdoors or with treated lumber? Yes. The Quik Guard coating is intended for indoor and outdoor applications, and supplementary product data also lists it as suitable for treated lumber.