Osprey Viper 3 Hydration Pack, Orange, One Size Hydraulics™ LT 2.5-liter (85 fl. oz.) reservoir included Upper side compression straps Direct-access zipper path to reservoir compartment Front fabric shove-it pocket with zippered organization pocket LidLock™ helmet attachment Blinker light attachment (light not included) Stretch-mesh harness pocket Magnetic sternum strap bite valve attachment