The Earth Pak Waterproof Dry Bag is a 30L liter backpack sack with a roll top closure, featuring adjustable straps for convenience. Made of durable PVC material, this original dry bag design includes a snap closure. With a compact size of 15"W x 26"H and weighing just 13.6 ounces, this Earth Pak backpack is lightweight and perfect for outdoor adventures in all weather conditions.