Simpson Strong-Tie Deck-Drive DCU COMPOSITE Screw, #10 x 2-3/4-in. T20, Type 316, Tan, 350-Pack (DCU234P316TN)

Key Features

Built for Harsh Deck Jobs Type 316 stainless steel gives this composite decking screw severe-level corrosion resistance, which matters when the deck is exposed to chlorides, coastal air, or other tough outdoor conditions. Cleaner Composite Fastening The tri-lobe thread design, inverted upper threads, and cap head work together to reduce board damage, clear excess material, and help prevent mushrooming for a cleaner finished deck surface. Trex-Approved 2-3/4 In. Length This Simpson Strong-Tie composite screw uses a T20 6-lobe drive and the 2-3/4 inch length approved by Trex for Trex composite decking, making it a solid fit for deck board installation where finish and holding power both matter.

Overview

The Simpson Strong-Tie Deck-Drive DCU COMPOSITE Screw, #10 x 2-3/4-in. T20, Type 316, Tan, 350-Pack is a hand-drive composite decking screw built for fastening composite and PVC deck boards with a cleaner finished look. This is a composite decking screw designed for fastening composite deck boards. Model number DCU234P316TN. If you are building or resurfacing a deck and want a screw that drives clean, sits right, and holds up in aggressive outdoor conditions, this is the right kind of fastener to be looking at.

What separates this screw from a basic deck screw is how it handles composite material during installation. Simpson Strong-Tie uses a tri-lobe thread design to reduce damage to the board while driving, and the inverted upper threads clear excess material so the fastener leaves a cleaner finish instead of pushing material up around the head. That matters on composite decking, where sloppy fastening shows up fast and is hard to ignore once the whole deck is down.

The cap head is another jobsite-friendly detail. It is designed to prevent mushrooming and keep material from rising above the deck surface, which helps you get a smoother, more professional-looking installation without extra cleanup at every fastener location. On visible deck boards, that is not a small detail. It is the difference between a deck that looks dialed in and one that looks rushed.

The Type-17 point is built for fast starts and easier penetration into composite decking. In real use, that means less wandering at the surface and less fighting the screw to get it started cleanly. On repetitive deck fastening, little improvements like that save time, reduce frustration, and help keep spacing and alignment consistent from board to board.

This specific version is made from Type 316 stainless steel and finished in tan. Type 316 matters if the deck is going near chlorides or other harsher environments where higher corrosion resistance is worth paying for. The painted head is meant to blend with decking colors for a more concealed appearance, which is exactly what most deck builders and homeowners want on a finished composite deck.

Size-wise, this is a #10 x 2-3/4 inch screw with a 0.230 inch head diameter and a T20 6-lobe drive. The 2-3/4 inch length is listed as an approved fastener length by Trex for Trex composite decking. Simpson Strong-Tie also notes that the DCU line is engineered for all types of composite decking, so this is not a one-brand-only fastener even though the Trex approval is a useful confidence point.

For installers thinking in coverage, this pack includes 350 screws, which Simpson notes is enough for about 100 square feet of decking with framing at 16 inches on center spacing. That makes this pack size a practical fit for smaller sections, repairs, accents, stairs, or as a top-off box on a larger deck build.

Who should buy it? Contractors, remodelers, deck builders, and serious DIYers installing composite or PVC decking and who care about finish quality should be looking here first. If you are working in a harsher outdoor environment and want the added corrosion resistance of Type 316 stainless, this version makes more sense than a lower-grade alternative. It is a purpose-built fastening solution, not a generic screw trying to do deck work.

Cleaner Results on Composite Decking

This screw is built specifically for composite decking, so it addresses the finish problems that show up when standard screws are used on plastic-heavy deck boards.

• Cap head helps prevent mushrooming for a smoother deck surface
• Tri-lobe thread design reduces damage to the composite board while driving

Start Faster and Drive Cleaner

The point and thread design are there for a reason. On repetitive deck fastening, easier starts and cleaner chip removal make the whole job go smoother.

• Type-17 point penetrates composite decking with ease for fast starts
• Inverted upper threads clear excess material to improve finish quality

Match the Deck Instead of Fighting It

Visible fasteners are part of the finished look on a deck. This tan version is made to blend better with deck boards instead of standing out like bare metal hardware.

• Tan painted head is intended to coordinate with composite decking colors
• Available in color-matching painted-head stainless steel options across the DCU line

Corrosion Resistance for Tough Outdoor Exposure

Not every deck lives in a forgiving environment. This Type 316 stainless version is the one to choose when corrosion resistance is a real requirement, not just a nice extra.

• Type 316 stainless steel is suited for environments with chlorides
• Engineered for composite and PVC decking applications outdoors

What’s in the Box

• (350) Simpson Strong-Tie DCU composite decking screws, #10 x 2-3/4 in.
• (1) T20 driver bit

Key Specifications

Compatibility

Driver Bit Uses a T20 6-lobe drive. Replacement bit part number: BIT20T-2-R2. Screw Plug System Compatible with color-matching DCU Screw Plugs for a more concealed finished appearance. Decking Approval The 2-3/4 inch DCU length is an approved fastener by Trex for Trex composite decking.

Built For

Deck Building Composite Decking PVC Decking Remodeling General Contracting Outdoor Construction Deck Repairs DIY / Hobbyist

Pro Tip

If you are matching a finished deck color, confirm the board color against the screw head before opening all the boxes. With visible-face fastening on composite decking, the right head color makes a bigger difference than most people expect.

Tool Nut’s Take

Tool Nut’s Take

Simpson Strong-Tie Deck-Drive DCU COMPOSITE Screw Gets the Finish Right

This is the kind of composite deck screw you buy when you care how the deck looks after the last board is down, not just whether the fastener goes in.

• Who it’s for: Deck builders, remodelers, and serious DIYers installing composite or PVC decking, especially in tougher outdoor environments.
• Why it stands out: Type 316 stainless steel, Trex-approved 2-3/4 inch length, and a thread and head design that helps reduce mushrooming and board damage.
• Worth knowing: This is a visible fastener solution, so make sure the tan head is the color match you want for your board choice before you start driving hundreds of them.

Common Questions

• What is this screw designed for? It is designed for fastening composite decking boards and is also listed for roof sleeper assemblies in the DCU product family.
• Is this length approved for Trex decking? Yes. Simpson Strong-Tie states that the 2-3/4 inch DCU length is an approved fastener by Trex for Trex composite decking.
• What drive does it use? It uses a T20 6-lobe drive, and the replacement driver bit part number is BIT20T-2-R2.
• Why choose the Type 316 version? Type 316 stainless steel is intended for severe-level corrosion resistance and is especially suited for environments with chlorides.