The FastenMaster FMCTXCL-TX1LFENCB Cortex Hidden Fastening System delivers a seamless, professional finish for Coastal Bluff decking and beyond. Specifically designed to hide fasteners in composite, cap stock, and PVC boards, this kit creates a clean, edge-to-edge look that lasts as long as your deck.

Why this system stands out

• Completely concealed fasteners: Cortex hides screws across the entire deck—first and last boards, perimeter, and stairs—so your Coastal Bluff boards read as one continuous surface.
• Unified board appearance: plugs are crafted from the same material as leading deck boards, delivering a near-perfect seamless finish with grain alignment that matches the surrounding boards.
• Durable, maintenance-free plugs: once set, Cortex plugs expand and contract with the boards, eliminating the need for replacement over the project’s lifetime.
• Professional-grade installation: TORX ttap drive system paired with a high-strength setting tool makes fastener seating precise and consistent.
• Speed and convenience: plugs arrive pre-aligned on a collated strip, removing the guesswork and reducing installation time by roughly half versus loose-plug methods.
• Spotter Lid Installation Guide: ensures perfect fastener placement on scalloped Trex Enhance boards for flawless alignment and appearance.

What you get and how it works

• Designed to fasten 100 lineal feet of Trex Enhance Coastal Bluff decking—a complete, ready-to-install solution for a common project scope.
• Includes 224 2-1/2" carbon steel Cortex screws, 240 collated Cortex plugs, and 2 Cortex setting tools—everything you need to finish a Coastal Bluff deck with hidden fasteners from start to finish.
• Simple installation sequence: drive the Cortex fastener with the included setting tool to the perfect depth, align the grain on the Cortex plug, place the plug over the fastener hole, and tap to finish for a flush, professional look.

Who benefits most from Cortex on Coastal Bluff decks

• Professional deck installers seeking a fast, reliable hidden-fastener solution that maintains a consistent, premium appearance across joists, edges, and stairs.
• Homeowners tackling coastal environments where a durable, low-maintenance deck finish matters most.
• Renovations or new builds using Trex Enhance boards where a seamless, edge-to-edge aesthetic is a priority.

Practical tips to maximize results

• Plan fastener spacing with the collated strips to minimize rework and ensure uniform gaps.
• Use the Spotter Lid Guide on scalloped Trex Enhance Coastal Bluff boards to position fasteners precisely where you want them.
• Keep the alignment of grain on plugs consistent for a visually cohesive deck surface.