This Bag can constructed to hold saltwater or fresh water or some other drinkings.Collapsible and ultra light, fold it up when empty into smaller size for easy storage and carry, wearable thickening free hook designed, portable, can be hung on your backpack.It can weaken sunlight burn inner liquid directly. Made of clear, non-toxic, food-grade safe plastic.Reusable, convenient, durable, space saving, and non-toxic.