The 20L water hydration pack is made of 600D oxford that is leakproof, durable, and water-resistant. It offers a large main compartment, and a separate rear compartment also features a 3-liter water reservoir and tube that lets you drink while on the move. A breathable cotton back pad makes it comfortable to carry, you can be sure to stay hydrated on your next hike, jog, camping trip, cycling, etc.