KingCamp oxford Dry Sacks are made of nylon fabric with PU coating. Roll-top dry sack must be closed properly to ensure water can't get in. Begin by folding the strip down first and be sure to have at least three rolls before closing the buckle. Avoid contact with sharp objects or subjecting the sack to high abrasion, as this could compromise the waterproof fabric. For maximum protection, the use of a waterproof hard case should be considered.