FASTENMASTER Cortex 2-1/2" Fastening System for Trex Decking - 100 Linear Feet - Trex Select Pebble Grey

Purchased this to use in the installation for picture framing of a deck. Easy to install with some issues to be aware of that are not in the instructions. I used this with TimberTech Pro Terrain product containing a scalloped bottom. Company does not recommend the use of Cortex with this product, but it can be used very successfully with care. You have to place the screws into the center of the scallops to ensure that when the screw is set below the surface enough to allow room for the plug, you have enough material to hold the board to the deck. I measured carefully each screw location, and by doing that, this product worked great for installing boards where I could not use the hidden fastening system.Ensure when installing it into your deck that you have wood underneath the screw for its full length. If you only have 1 1/2" inches of wood, which is not enough, it will not set properly and either remain flush with the surface of the deck or not fully set below the surface allowing room for the plug. You either need to add additional lumber underneath the screw, or press hard directly over the screw to force it to drill deeper. Either solution is not ideal, but both solutions work. It all depends on your access to the underside of the deck.If the screw only goes part way and does not countersink to the full depth, the plug can be trimmed shorter to fit and when tapped into place will still look great.With these minor cautions, this product works great and produces a finished installed board that you can hardly tell where the screws are. The boards are solidly in place and look great. Color match of the plugs is outstanding.

Excellent fastening system! The plugs match the decking perfectly and the location of the screws virtually disappears when applied correctly. I installed them with an impact driver which worked very well.

This product is really great. Easy to use, durable almost invisible. Wish I had known about these earlier.

Perfect color ! Works great

These screws worked well on my new TREX deck. Make sure the screws are driven all the way down or the plugs that go on top will not seat fully. I had to remove a couple of plugs, trim the bottom of new plugs and replace them. I don't think they are designed to be removed so make sure the holes are drilled where you want them.

The ease to use and the match to the colors of our porch

The Cortex system works well and the plugs look great. However the screw heads strip easily.When installing my 4’ x 16’ deck I had pre-drilled all holes but 4 screws stopped flush with the composite decking.The screw heads strip easily when trying to back out or rework the screw. Now what?I’m going to try a screw extractor or drill out the screw head.

A little pricey but works great for my deck project