Lightweight Hydration Pack, Breathable Design * Adjustable from Small Children to Adult * Extremely Durable Design, Rip-stop Material.Lightweight and Adjustable for Children to Adult, Includes 1.5 Liter Bladder and is Compatible with Jetflow Bottle Hydration System * 1.5 Liter Bladder Included (Fits 2.0 Liter) * Jetflow Manifold Compatible