Fast Starts The SawTooth point gets this structural wood screw started quickly and cuts down installation effort. In most wood-to-wood jobs, that means less fighting the screw and less need to predrill. Strong Hold A bold thread pattern is built for serious grab in wood and engineered wood. That gives the Simpson Strong-Tie SDWS22400DB-R50 timber screw the pull-through resistance and holding power you want in structural connections. Positive Drive The T40 6-lobe drive gives better bit engagement than a typical lag-style fastener. That helps reduce cam-out, improves bit life, and makes long screws easier to run home.
The Simpson Strong-Tie SDWS22400DB-R50 Strong-Drive SDWS Timber Screw is a 4 inch exterior structural wood screw sold in a 50-count pack for wood-to-wood fastening. This is a timber screw designed for structural wood-to-wood connections in exterior and treated wood applications. Model Number: SDWS22400DB-R50. If you want a faster, easier alternative to through-bolting or traditional lag screws, this is the kind of fastener that saves time without giving up holding strength.
For this specific version, you are getting a #12 x 4 in. screw with a 0.220 in. shank diameter, 2-3/8 in. thread length, and a large 0.760 in. washer head. Those numbers matter because they explain why this fastener works well for ledgers, rails, posts, pergola members, planter boxes, and other structural wood connections where you need solid clamping and a broad bearing surface at the head. The larger head spreads load over more wood, which helps when fastening dimensional lumber and structural members together.
One of the biggest advantages here is the installation behavior. Simpson uses a SawTooth point that helps the screw bite quickly, reduce installation torque, and eliminate predrilling in most applications. On the job, that means quicker starts, fewer stalls, and less time spent swapping between drill bits and drivers. The underhead nibs are there for a reason too: they help the washer head seat flush with less splintering at the surface, so the finished connection looks cleaner and tightens down more consistently.
The drive system is another practical upgrade over old-school lag screws. This fastener uses a T40 6-lobe drive for more positive engagement under load. When you’re driving a long structural screw into dense lumber, good bit engagement matters. It helps keep the bit planted, reduces the chance of stripping the recess, and generally makes the whole process less aggravating, especially when you’re working overhead or out at arm’s length.
Material and coating matter just as much as the thread pattern, especially outdoors. This screw is steel with Simpson’s double-barrier coating, which is rated for corrosion resistance equivalent to hot-dip galvanization and is intended for certain exterior and preservative-treated wood applications as described by the evaluation report. For deck-related work, fence construction, outdoor framing, and other exposed wood projects, that coating is the difference between a structural fastener that belongs outside and one that does not.
The Simpson Strong-Tie SDWS22400DB-R50 is also code-focused hardware, not just a generic construction screw with a big head. Simpson positions the SDWS line as a high-strength structural fastening option for common wood framing applications, including structural wood and engineered wood connections, ledgers, and even mass timber connection uses within the broader product family. For contractors, remodelers, and serious DIY users, that means you are buying a purpose-built structural fastener from a manufacturer that lives in this category.
This screw is best for users who want faster structural fastening in wood without the hassle of through-bolts or lag screws. Fence builders, deck builders, pergola installers, general contractors, and DIY homeowners working on serious outdoor wood projects are the right audience. If your work is mainly wood-to-wood fastening and you need exterior-grade corrosion resistance, strong pull-down, and easier driving, this is a smart choice.
This screw is made for real structural wood work, not light trim duty. In fence and railing builds, it gives you a quicker way to pull members together without messing with lag screws and pilot holes in most cases.
The large washer head is one of the reasons this fastener works so well in structural lumber. It spreads clamping force across more surface area, which helps the connection pull down tight and stay supported at the face of the wood.
Outdoor wood construction needs the right coating as much as the right thread. The double-barrier coating makes this screw suitable for certain exterior and preservative-treated wood applications, which is exactly where a regular interior screw comes up short.
| Application | Wood-to-Wood Fastening |
|---|---|
| Length | 4 in. |
| Shank Diameter | 0.220 in. |
| Head Diameter | 0.760 in. |
| Thread Length | 2-3/8 in. |
| Drive Type | T40 6-Lobe |
| Head Type | Washer Head |
| Coating / Material | Double-Barrier Coated Steel |
| Point Type | SawTooth Point |
| Color | Tan |
| Package Quantity | 50 |
| Fastener Size | #12 x 4 in. |
Driver Interface Uses a T40 6-lobe drive. Simpson lists replacement driver bit BIT40T-134-R2. Material Use Designed for wood-to-wood fastening, including structural wood and engineered wood applications within the SDWS line. Exterior Use Double-barrier coating is intended for certain exterior and preservative-treated wood applications as described in the evaluation report.
Deck Building Fence Construction Pergolas Planter Boxes General Contracting Remodeling Exterior Wood Framing DIY / Hobbyist
If you’re driving these into dense treated lumber, keep steady pressure on the T40 bit and let the SawTooth point do the work. That usually gives you a cleaner start and helps the washer head seat flush without chewing up the drive recess.
Tool Nut’s Take
This is the kind of exterior structural screw that makes you wonder why you’d still reach for lag screws on a lot of wood-to-wood jobs.
More styles you’ll love.
Reviews (0)
There are no reviews yet.