Water-resistant and DURABLE. The backpack is made from highly rip and water-resistant nylon fabric, which provides strength and long-lasting performance, with minimal weight. Stress points are reinforced with bar tacking for increased longevity. We use durable 2-way Abrasion Resistant SBS Metal Zippers across the backpack. COMPACT. Folds into zippered inner pocket to fit anyw. Unfolds from pocket to backpack. A must-have on any trip. LIGHTWEIGHT(0.46 Pounds) and ROOMY(20 Liters). A true space saver. Stuff the bag into its own pocket for storage and unzip it when you reach your destination. Avoid overweight baggage charges by simply unfolding it from your luggage and using it as a carry on for your excess baggage.