100% waterproof, all seams are electronically heat welded. Made from durable UV Coated 24 oz. Tarpaulin PVC. Water tight roll closure with quick release buckles. Bag can seal in two different closure methods, over the top or down the sides. Extra-large buckle ensures roll stays closed in all environments. Air purge valve makes for compression easy. Reflective webbing and external bungee storage system. Inner sleeve to hold most folders, notebooks, tablets and up to 15” laptops. Included quick-release buckles convert bags into the perfect waterproof tail packs. Removable MOLLE panel is reversible with waterproof document/map pocket. Integrated front pocket to hold optional hydration bladder (CL-HYDRO-S not included). Two side mesh pockets large enough to hold 30 oz. fuel bottles (bottles not included). Backpack straps are 3-way adjustable and padded for comfort. Padded back panel with airflow system.