The Simpson Strong-Drive DWP Wood Screw in #12 x 2-1/2", Type 316 Stainless Steel with Flat Head is a load-rated structural fastener engineered for demanding exterior applications where corrosion resistance and verified performance data are non-negotiable. Designed specifically for decks, docks, boardwalks, and outdoor structures exposed to moisture and corrosive environments, this flat-head wood screw delivers the combination of structural integrity and long-term durability that seaside and waterfront projects require. With its sharp point, proprietary box-thread design, and T27 6-lobe drive, it drives cleanly into wood and engineered wood products while meeting ICC-ES acceptance criteria AC233 for shear, pull-through, and withdrawal resistance.

Key Features

• Type 316 Stainless Steel construction - provides superior resistance to saltwater, chlorides, and harsh outdoor environments, making it the right choice for seaside decks, docks, and marine-adjacent structures where standard stainless or galvanized fasteners may fall short.
• Unique box-thread design with raised-ridge technology - greatly reduces driving torque so installers can drive more screws per battery charge, increasing efficiency on large-scale deck and dock projects.
• Specially designed sharp point - penetrates hardwood and engineered wood products with ease, reducing the need for pre-drilling and speeding up installation time.
• T27 6-lobe drive - provides a secure bit fit that minimizes cam-out, resulting in a smooth, controlled drive and extended bit life on long projects.
• Flat head profile (0.435 in. head diameter) - sits flush with the surface for a clean, professional finish on deck boards and exterior structural connections.
• ICC-ES AC233 load-rated for shear, pull-through, and withdrawal - meets recognized structural performance criteria so engineers, inspectors, and contractors can specify and verify this fastener with confidence.
• Compatible with wood, engineered wood, and polymer materials - versatile enough to handle a wide range of exterior substrates common on decks, boardwalks, and docks.

Why This Product

• Built for high-corrosion and severe-exposure environments - Type 316 stainless steel offers a higher grade of corrosion protection than Type 304, making this screw a dependable fastener for waterfront structures, coastal decks, and areas exposed to salt air or chemical exposure.
• Load-rated for structural applications - tested and rated for shear, pull-through, and withdrawal resistance per ICC-ES AC233, giving builders and inspectors the documented performance data needed for engineered structural connections.
• Engineered to reduce installer fatigue on large jobs - the box-thread design reduces driving torque, which extends battery runtime and lessens physical strain when fastening hundreds of deck boards or dock planks in a single day.
• Trusted Simpson brand quality - designed by a recognized name in structural connectors and fasteners, this screw is a purposeful solution for exterior projects where both performance and corrosion protection must be verified.

Specifications

• Brand: Simpson Strong-Tie
• Screw Size: #12
• Length: 2-1/2 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 316 Stainless Steel
• Finish: Type 316 Stainless Steel
• Approx. Count Per Lb: 56
• Country of Origin: Taiwan

Available Pack Options

• T12250WP1: 1 Lb (56) - includes (1) T27 6-lobe driver bit
• T12250WP5: 5 Lb (280) - includes (1) T27 6-lobe driver bit
• T12250WPB: 1750 Pk - includes (2) T27 6-lobe driver bits

Frequently Asked Questions

What makes Type 316 stainless steel different from other stainless finishes for outdoor fasteners?

Type 316 stainless steel contains molybdenum, which gives it enhanced resistance to chlorides, saltwater, and corrosive chemicals compared to standard stainless grades. This makes it particularly suited for docks, boardwalks, and decks in coastal or waterfront settings where exposure to salt air or moisture is constant and severe corrosion is a real concern.

Is this screw load-rated for structural applications?

Yes. The Strong-Drive DWP Wood SS flat-head screw has been tested in accordance with ICC-ES acceptance criteria AC233 and is load-rated for shear, pull-through, and withdrawal resistance. This makes it appropriate for engineered structural exterior connections where documented performance values are required.

What drive bit does this screw require?

This screw uses a T27 6-lobe drive, also known as a Torx T27 bit. The 6-lobe design provides a secure, positive engagement between the bit and the screw head, which minimizes cam-out and contributes to longer bit life during extended installation.

What materials can this screw be used with?

The Strong-Drive DWP Wood SS is designed for use with wood, engineered wood, and polymer materials. Its sharp point and box-thread design allow it to penetrate hardwood and composite products without pre-drilling in many applications, making it a practical choice for deck boards, dock planks, and similar exterior substrates.

Note: Product dimensions may differ from picture.