Simpson Deck-Drive DCU Composite Screw in #10 x 2-3/4" with Gray 05 color-matched cap head is a Type 316 stainless steel fastener engineered specifically for composite and PVC decking installations where severe corrosion resistance is required. Built by Simpson for demanding outdoor environments including coastal and marine applications, this screw combines a Type-17 point for clean penetration, inverted upper threads that clear excess material, and a painted cap head that blends seamlessly with popular composite decking manufacturers' colors - delivering a professional, concealed finish alongside long-term durability in chloride-rich and salt air conditions.

Key Features

• Type 316 Stainless Steel material - provides severe-level corrosion resistance, making it the right choice for marine, coastal, and salt air environments where standard fasteners fail prematurely
• Type-17 Point - penetrates composite and PVC decking cleanly without pre-drilling, reducing installation time and effort
• Inverted upper threads - clear excess composite material during installation, ensuring a secure, clean seating without surface distortion
• Tri-Lobe thread design - creates a strong, reliable hold in composite decking material for a secure, lasting installation
• Cap Head with Gray 05 color-matching paint - blends with popular decking manufacturers' products for a more concealed, professional appearance that doesn't draw attention to fasteners
• T20 6-Lobe drive type - provides positive bit engagement and reduced cam-out during driving, improving control and efficiency on the job
• 0.230" head diameter - sized to seat flush with composite decking surfaces for a clean, finished look
• 2-3/4" length - engineered to achieve proper penetration depth for composite deck board fastening applications

Why This Product

• Designed specifically for composite and PVC decking, the DCU eliminates the need to source multiple screw types - one engineered screw handles the full range of composite deck board installations cleanly and securely
• Type 316 stainless steel construction makes this screw the right fastener for coastal, marine, and high-chloride environments where corrosion resistance is not optional but essential to long-term deck performance
• The Gray 05 color-matched painted head blends with popular composite decking brands, creating a polished, professional finish where fasteners remain discreet rather than visually prominent
• The combination of a Type-17 point and inverted upper threads means the screw does the work cleanly - penetrating composite material without excessive force and clearing debris for a flush, secure installation every time

Specifications

• Brand: Simpson Strong-Tie
• Screw Size: #10
• Length: 2-3/4 in.
• Head Diameter: 0.230 in.
• Head Type: Cap Head
• Drive Type: T20 6-Lobe
• Thread Type: Tri-Lobe Threads
• Point Type: Type-17 Point
• Material: Type 316 Stainless Steel
• Finish: Type 316 Stainless Steel
• Color: Gray 05
• Country of Origin: Vietnam

Available Pack Options

• DCU234P316GR05: 350 Pk - includes 1 driver bit included
• DCU234MB316GR05: 1750 Pk - includes 2 driver bits included

Approved Applications

• Marine
• Decks - Deck Boards Composite
• Coastal / Salt Air

Frequently Asked Questions

Why is Type 316 stainless steel recommended for composite deck fastening in coastal or marine environments?

Type 316 stainless steel provides severe-level corrosion resistance and is especially suited for applications in environments with chlorides, such as coastal, salt air, and marine installations. Standard fasteners can corrode rapidly in these conditions, compromising the structural integrity of the deck over time. The 316 alloy is formulated to withstand these aggressive exposures for lasting performance.

What makes the DCU composite screw compatible with so many composite decking brands?

The Deck-Drive DCU is engineered for all types of composite and PVC decking and features a Type-17 point and Tri-Lobe threads designed to penetrate and hold in composite materials cleanly. The Gray 05 color-matching painted cap head is designed to blend with popular decking manufacturers' products, reducing the need to match different screws to different deck board brands.

What driver bit is compatible with this screw?

This screw uses a T20 6-Lobe drive. The compatible replacement driver bit is the BIT20T-2-R2, which is available separately.

What do the inverted upper threads on the DCU screw do?

The inverted upper threads are engineered to clear excess composite material as the screw is driven, preventing buildup around the fastener head. This results in a clean, flush installation with a smooth surface around each screw - contributing to both the appearance and the secure seating of the fastener in the composite deck board.

Downloads and Resources

• Composite-Decking Color Cross-Reference Chart

Related Products

• - Compatible T20 6-Lobe driver bit
• Deck-Drive Screw Plug Solution - Compatible color-matching DCU screw plugs