All of Granulated Activated Carbon (GAC) Systems are filled with the finest Coconut Shell Carbon on the market today. Our Carbon does carry the NSF Certification and s designed for the beverage industries. When you want the very best for your brews, Craft Brew Water's Carbon Systems deliver. Combined with the Craft Brew Reverse Osmosis System, you have the confidence and control over your brewing water. If you need help with sizing your system, call us anytime.