The SJ Ultra Vest has 9.2 liters of storage capacity in a super lightweight package. It comes in at 8.2 ounces (233 grams) – without the two 20 fluid oz bottles. What makes the vest super lightweight and strong is the use of Cuben Fiber. Cuben Fiber is lightweight, highly durable, and is 50-70% lighter than Kevlar, four times stronger than Kevlar, and allows flex without losing strength. It is also less than half the weight of silnylon, has low specific gravity (floats on water), high chemical resistance, excellent UV resistance and is 100% waterproof. The vest is structured with the Hex Mesh allowing it to breathe while providing durability and anti-moisture absorbing properties in a lightweight package. All the pockets are constructed of a stretchy material that expands with your increased loads while keeping smaller loads from bouncing around when running. Watch out for the sizing. The Ultra Vest is based on chest sizing so measure accordingly. Used only a few times. In excellent condition.