Simpson Deck-Drive DCU Composite Screw in #10 x 2-3/4", Red, Type 305 Stainless Steel is engineered specifically for composite and PVC decking installations where a clean, professional finish and reliable corrosion resistance are essential. Crafted from Type 305 stainless steel, these cap-head fasteners are particularly well-suited for decking environments exposed to chlorides - including coastal and high-humidity settings - where standard screws would degrade over time. The color-matched red painted head blends seamlessly with popular composite decking brands, keeping fasteners visually concealed for a refined, finished look on any deck surface.

Key Features

• Type 305 Stainless Steel construction - delivers strong corrosion resistance in composite decking environments, including areas exposed to chlorides such as coastal or poolside applications, so fasteners maintain their integrity over time
• Type-17 Point - penetrates composite decking cleanly without pre-drilling, reducing installation time and effort while minimizing surface damage
• Inverted upper Tri-Lobe Threads - engineered to clear excess material as the screw seats, resulting in a clean, flush installation without mushrooming or surface buildup around the fastener
• T20 6-Lobe drive - provides superior torque transfer and reduces cam-out during driving, giving installers better control and a more consistent result across an entire deck board run
• Cap Head design with 0.230 in. head diameter - sits low and flush against composite decking surfaces, contributing to the smooth, professional appearance of finished deck boards
• Color-matching red painted head - visually integrates with popular manufacturers' composite decking products, creating a more concealed fastening system that enhances the overall aesthetic of the completed deck
• 2-3/4 in. length in #10 screw size - sized for reliable penetration depth and holding strength in composite decking applications without over-penetrating substructure materials

Why This Product

• Designed from the ground up for composite and PVC decking - the Type-17 point and Tri-Lobe threading work together to drive cleanly through composite material without the cracking, mushrooming, or surface damage that can result from using general-purpose screws
• Type 305 stainless steel is especially suited for chloride-rich environments, making this screw a dependable choice for deck projects near saltwater, pools, or other areas where corrosion is an ongoing concern
• The red color-matching painted head eliminates the visible fastener look common with standard silver or zinc screws, giving composite deck surfaces the clean, uniform appearance that professional installations demand
• The T20 6-Lobe drive reduces cam-out and slippage during installation, helping maintain consistent countersink depth across every board - a practical advantage when driving large numbers of fasteners on a full deck project

Specifications

• Brand: Simpson Strong-Tie
• Screw Size: #10
• Length: 2-3/4 in.
• Material: Type 305 Stainless Steel
• Finish: Type 305 Stainless Steel
• Color: Red
• Head Type: Cap Head
• Head Diameter: 0.230 in.
• Drive Type: T20 6-Lobe
• Thread Type: Tri-Lobe Threads
• Point Type: Type-17 Point

Available Pack Options

• DCU234P305RD: 350 Pk - includes 1 driver bit included
• DCU234MB305RD: 1750 Pk - includes 2 driver bits included

Approved Applications

• Decks - Deck Boards Composite

Frequently Asked Questions

Why are these screws recommended for environments with chlorides?

These screws are made from Type 305 stainless steel, which provides corrosion resistance in settings where chlorides are present - such as coastal areas, poolside decks, or regions where road salts may be a factor. The stainless steel material resists oxidation and surface degradation that would compromise a standard coated screw over time in those conditions.

What is the purpose of the Tri-Lobe threading and inverted upper threads?

The Tri-Lobe thread profile, combined with the inverted upper threads, is engineered to clear excess composite material as the screw is driven. This prevents the buildup and surface mushrooming that can occur around fastener heads in composite decking, resulting in a clean, flush, and secure installation.

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 designed to work with the Deck-Drive DCU composite screw for consistent torque and reduced cam-out during installation.

How does the color-matching painted head work with composite decking?

The painted cap head is color-matched to blend with popular composite decking manufacturers' products. Because the head sits flush against the board surface at only 0.230 in. in diameter, it becomes visually integrated into the deck surface rather than standing out, giving the finished deck a more polished and professional appearance. Refer to the Composite-Decking Color Cross-Reference chart in the Downloads section to match the correct screw color to your specific decking product.

Downloads and Resources

• Composite-Decking Color Cross-Reference chart

Related Products

• Deck-Drive Screw Plug Solution