With the Osprey Duro/Dyna Belt Trail Running Pack you get the space you need to carry the essentials for your next trail run. Two soft flasks for carrying water are also included. Extra pockets provide plenty of accessible space for your phone, gels, and a safety whistle. The design is ergonomic and fits comfortably around your waist and hips. You can even carry hiking poles or outerwear with the external storage loops. This bag may be small, but it sure is mighty.