The Simpson Deck-Drive DCU Composite Screw in #10 x 2-3/4" with Type 316 Stainless Steel finish is a premium fastener engineered by Simpson for reliable, long-lasting performance in composite and PVC decking installations. Designed to deliver severe-level corrosion resistance, this screw is especially well-suited for coastal environments, poolside decks, and any application where exposure to chlorides, saltwater, or harsh weather conditions demands a fastener that won't fail over time. The Type 316 stainless steel construction goes beyond standard corrosion protection, making it a trusted choice for marine-adjacent and high-humidity outdoor settings where lesser materials would corrode prematurely.

Key Features

• Type 316 Stainless Steel material - provides severe-level corrosion resistance ideal for chloride-heavy environments such as coastal, marine, and poolside decking applications
• Type-17 Point - penetrates composite and PVC decking cleanly without pre-drilling, speeding up installation and reducing labor time
• Inverted upper Tri-Lobe threads - clear excess material from the entry point as the screw drives in, resulting in a flush, clean, and secure finish with no raised crowning or surface damage
• T20 6-Lobe drive type - provides superior torque transfer compared to Phillips or square drives, reducing cam-out and driver bit wear for more consistent, controlled installations
• Cap Head design with 0.230 in. head diameter - sits flush against decking surfaces for a professional, low-profile appearance that resists snagging and wear underfoot
• #10 x 2-3/4" size - engineered for the typical thickness range of composite and PVC decking boards, ensuring proper engagement and holding strength without over-penetrating
• Available with color-matching painted heads - allows the fastener to blend with popular composite decking manufacturers' colors for a more concealed, professional finish

Why This Product

• Purpose-built for composite and PVC decking, this screw eliminates the need to mix and match different fasteners across a deck project - one screw handles all composite decking types, simplifying procurement and installation
• The Type 316 stainless steel finish delivers severe-level corrosion protection that exceeds standard stainless grades, making it the right choice for environments where chlorides and salt air would degrade a typical fastener over time
• The combination of a Type-17 point and inverted upper Tri-Lobe threads is specifically engineered to penetrate composite materials cleanly and clear debris as the screw seats, reducing the risk of surface damage or raised heads that are common with general-purpose screws
• Color-matching painted head options mean the same high-performance screw can be used on finished deck surfaces where a concealed, professional appearance matters - without compromising structural integrity or corrosion resistance

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: None

Available Pack Options

• DCU234C316: 70 Pk - includes 1 driver bit included
• DCU234P316: 350 Pk - includes 1 driver bit included
• DCU234MB316: 1750 Pk - includes 2 driver bits included

Approved Applications

• Composite decking installation in residential and commercial outdoor settings
• PVC decking fastening where a clean, flush finish is required
• Coastal, marine, and poolside deck construction where chloride exposure demands severe-level corrosion resistance
• High-humidity and wet-environment decking applications where standard stainless or coated screws may fail prematurely

Frequently Asked Questions

Why is Type 316 stainless steel recommended for composite decking in coastal or poolside environments?

Type 316 stainless steel contains molybdenum, which significantly improves resistance to chloride-induced corrosion compared to standard 304 stainless steel. This makes the DCU screw in 316 stainless the appropriate choice for decks exposed to salt air, ocean spray, pool chemicals, or other chloride-rich conditions where a lesser fastener would corrode and stain the decking surface over time.

Do I need to pre-drill composite decking before using these screws?

No. The DCU screw is engineered with a Type-17 point specifically designed to penetrate composite and PVC decking materials without requiring a pilot hole. This reduces installation steps and speeds up the overall decking process.

What driver bit is compatible with the T20 6-Lobe drive on these screws?

These screws require a T20 6-Lobe driver bit. The compatible replacement driver bit is the BIT20T-2-R2, which is sold separately.

Can the Deck-Drive DCU screw be used with a color-matched plug or cap system for a concealed finish?

Yes. The DCU screw is compatible with color-matching painted head options as well as the Deck-Drive Screw Plug Solution, which allows the fastener to blend with popular composite decking manufacturers' colors for a more professional, concealed appearance on finished deck surfaces.

Downloads and Resources

• Composite-Decking Color Cross-Reference chart

Related Products

• BIT20T-2-R2 - Compatible T20 6-Lobe driver bit
• Deck-Drive Screw Plug Solution - Compatible color-matching screw plugs for a concealed finish