18 oz PVC/polyester Heavy-duty construction, welded seams Fold-down StormStrip closure Quick-release buckle D-ring attachment point NRS Tuff Sack Dry Bag - Drop your gear in the NRS Tuff Sack, fold down the watertight closure and forget about it. Professional outfitters around the globe rely on NRS Tuff Sacks to keep gear dry. Designed in a variety of sizes, the Tuff Sack can fit everything from sunscreen and on-the-boat essentials to clothing for a week.