1.5 Liter (50 oz) Hydration Bladder Included, Fits a 2 Liter (68 oz), Also accepts Jetflow Manifold * Dobby Diamond Ripstop Construction, Zipped Front Pocket Storage with MP3 Access * Bullet Bite Valve, Adjustable Sternum Strap, Reflective Taping * Padded Ventilated Back Panel, Active Suspension Harness