The Simpson Strong-Drive DWP Wood Screw in #12 x 3-1/2", Type 305 Stainless Steel with a Flat Head is a load-rated structural fastener engineered for deck, dock, boardwalk, and general exterior applications where reliable corrosion resistance and certified performance are required. Designed with a sharp point and unique box threads, this exterior wood screw delivers superior pull-through, shear, and withdrawal resistance - making it a trusted choice for structural connections exposed to moisture, humidity, and harsh outdoor conditions.

Key Features

• Type 305 Stainless Steel construction - provides strong corrosion protection for exterior environments, including docks, boardwalks, and decks exposed to high or severe corrosion conditions.
• Unique box thread design with raised-ridge technology - greatly reduces driving torque so you can drive more fasteners on a single battery charge, improving efficiency on large exterior projects.
• Specially designed sharp point - penetrates hardwood and engineered wood products with ease, reducing the need for pre-drilling and speeding up installation.
• T27 6-Lobe drive - provides a secure bit fit for easier driving and extended bit life, minimizing cam-out and reducing bit replacement costs on the job.
• Flat head profile - sits flush with the material surface for a clean, professional finish in deck, dock, and exterior structural applications.
• Tested to ICC-ES AC233 acceptance criteria - load-rated for shear, pull-through, and withdrawal resistance so you can specify these fasteners with confidence in engineered structural connections.
• Compatible with wood, engineered wood, and polymer materials - offers versatility across a wide range of exterior structural applications.

Why This Product

• Built for high-corrosion exterior environments - the Type 305 Stainless Steel material resists degradation in wet, humid, and severe corrosion conditions, making this screw a reliable choice for docks, boardwalks, and waterside decks where standard fasteners would fail prematurely.
• Certified load ratings remove guesswork - tested and load-rated per ICC-ES acceptance criteria AC233 for shear, pull-through, and withdrawal resistance, giving contractors and engineers verified performance data for structural connections.
• Reduced driving effort means faster project completion - the box thread design lowers driving torque, so you get more fasteners driven per battery charge and spend less time on the tool, especially on large decking or dock projects.
• Sharp point works across multiple material types - designed to penetrate hardwood, engineered wood, and polymer materials without pre-drilling, reducing labor steps and keeping exterior structural work moving efficiently.

Specifications

• Brand: Simpson Strong-Tie
• Screw Size: #12
• Length: 3-1/2 in.
• Head Type: Flat Head
• Head Diameter: 0.435 in.
• Drive Type: T27 6-Lobe
• Thread Type: Box Threads
• Point Type: Sharp Point
• Material: Type 305 Stainless Steel
• Finish: Type 305 Stainless Steel
• Approx. Count Per Lb: 42
• Country of Origin: Taiwan

Available Pack Options

• S12350WP1: 1 Lb (42) - includes (1) T27 6-lobe driver bit
• S12350WP5: 5 Lb (210) - includes (1) T27 6-lobe driver bit
• S12350WPB: 1000 Pk - includes (2) T27 6-lobe driver bits

Frequently Asked Questions

What applications are these screws designed for?

The Strong-Drive DWP Wood SS screw is designed for deck, dock, boardwalk, and general exterior structural applications where extra corrosion protection and verified load performance are required - particularly in environments near water or where high or severe corrosion exposure is expected.

What materials can these screws be used with?

These fasteners are compatible with wood, engineered wood, and polymer materials, making them a versatile option for a wide range of exterior structural connections.

Are these screws load rated for structural use?

Yes. The Strong-Drive DWP Wood SS flat-head screws have been tested in accordance with ICC-ES acceptance criteria AC233 and are load rated for shear, pull-through, and withdrawal resistance, making them suitable for engineered structural connections.

What drive bit is required for these screws?

These screws use a T27 6-Lobe drive, which provides a secure bit fit for easy driving and extended bit life, helping reduce cam-out during installation.

Note: Product dimensions may differ from picture.