1.5L NATHAN x HydraPak QuickStart Bladder with Push-Pull Bite Valve for easier drinking and removal for cleaning; Designed with adjustable front and side straps to comfortably fit a wide range of body types; Three expandable power mesh pockets on the front straps; Large back pocket and separate bladder compartment with hook and loop keepers; Rear stretch mesh pocket fits layers, gear, and larger essentials, plus an elastic pole keeper; Reflective details enhance visibility in low-light conditions; Front flask pocket holds up to one 20oz/591ml soft flask (sold separately)