Port Authority C-FREE Snag-Proof 1/4-Zip Our C-FREE carbon neutral -zip not only feels good, it does good. With C-FREE, we measured the carbon footprint of these styles and we're neutralizing their impact with Carbonfree certification. 5.9-ounce, 100% recycled polyester jersey. Snag-proof. Moisture-wicking. Cadet collar. Covered, dyed-to-match zipper with gunmetal pull. Self-fabric cuffs.