The Simpson Strong-Tie SDS25312 Strong-Drive SDS Heavy-Duty Connector Screw is a 1/4 inch x 3-1/2 inch structural wood screw built for connector installation, wood-to-wood fastening, and engineered wood applications. This is a heavy-duty connector screw designed for fastening structural connectors and wood members without predrilling. Model Number: SDS25312. For contractors, deck builders, framers, and serious DIY users, the big deal here is faster installation with less chance of splitting the wood.

This screw uses a Type-17 point, which matters because it starts easier and drives with less effort than a standard point. On the job, that means you spend less time fighting the fastener and more time getting hardware installed. The serrated threads help the screw bite and pull tight, while the partially threaded 2-1/4 inch thread length is set up to clamp materials together effectively in structural fastening applications.

The head design is just as important as the point. Simpson Strong-Tie uses a 3/8 inch hex head with a 0.500 inch integrated washer, so you get a broad bearing surface that seats firmly against connectors and wood. That helps spread load at the contact point and gives you a more confident fit in heavy-duty connector work. The head is also stamped for identification after installation, which is useful when you're inspecting finished work or matching installed hardware later.

For exterior projects, the double-barrier coating is the detail that makes this version the right pick over a basic interior fastener. It is intended for exterior use and helps resist corrosion in exposed jobsite conditions. If you are working on decks, outdoor structures, or other wood framing that sees weather, this coating is a real buying factor, not just a line in the spec sheet.

The SDS25312 is a 1/4 inch diameter fastener with a 3-1/2 inch overall length, 10 threads per inch, and a listed shank diameter of 0.235 inch in Simpson Strong-Tie product data. That combination puts it squarely in the structural screw category, not the everyday construction screw category. It is meant for stronger connections where hardware and fastener performance both matter.

Installation is straightforward. Simpson Strong-Tie recommends a low-speed 1/2 inch drill with a 3/8 inch hex driver. That tells you this screw is designed around controlled driving torque, not high-speed drywall-style installation. If you're driving a lot of them into framing or connector hardware, using the recommended setup will make the process smoother and help the washer head seat correctly.

Compatibility is simple and practical. The screw uses a standard 3/8 inch hex drive interface, and Simpson Strong-Tie lists replacement driver bit model BITHEXR38-R1. That means you are not locked into a weird proprietary driving setup, and replacing a worn bit is easy. The screw is also specifically intended for heavy-duty Simpson Strong-Tie connectors, which makes it a direct fit for many structural connector installations.

Who should buy it? If you install Simpson Strong-Tie connectors, build decks, handle framing repairs, or need a structural fastener that drives faster than lag screws without the hassle of predrilling, this is the right kind of screw. The Simpson Strong-Tie SDS25312 Strong-Drive SDS Heavy-Duty Connector Screw makes the most sense for users who care about structural performance, fast installs, and exterior durability more than bargain-bin fastener pricing.

Simpson Strong-Tie SDS25312 Strong-Drive SDS Heavy-Duty Connector Screw Gets Structural Work Done Faster

If you want structural screw performance without the drag of predrilling every hole, this is the fastener to reach for.

• Who it's for: Deck builders, framers, remodelers, and anyone installing Simpson connector hardware or making serious wood-to-wood structural connections.
• Why it stands out: The Type-17 point, serrated threads, and integrated washer head make it quicker to drive and better suited to connector work than a generic structural screw.
• Worth knowing: This is a bulk 900-count box, so it makes the most sense if you burn through fasteners regularly. Also, keep the right 3/8 inch hex driver on hand because the replacement bit is not included.

• Does this screw require predrilling? No. Simpson Strong-Tie states the Type-17 point is designed for easy driving with no predrilling and minimal splitting.
• What tool should be used to install it? Simpson Strong-Tie recommends a low-speed 1/2 inch drill with a 3/8 inch hex driver.
• Is this screw intended for exterior use? Yes. The SDS25312 uses a Double-Barrier Coating and is listed for exterior applications.
• What materials is it designed to fasten? It is intended for heavy-duty connector installations, wood-to-wood fastening, and engineered wood applications.