Osprey has always been known for its excellent fit. No wonder their running pack grabs your body in such an excellent fashion. This model includes two 500 ml soft flasks. NOTE! The hydration bag/hose seen in some images is not included. - Women's carrying system, the men's version is called Duro 6 - Zippered front pocket with key clip - Bottle pockets at the front - Compatible with Hydraulics hydration bags - Includes two 500 ml soft bottles - Stretchy mesh side pocket - LED light holder - Stow-on-the-Go pole holders can be used without taking the pack off your back - Made of 70 x 140 denier ripstop Nylon - *Choose size according to chest circumference:* - 65 - 75 cm --> S - 75 - 90 cm --> M - 90 - 105 cm --> L