If you are on the road for a longer period of time, you also want to take some extra stuff with you. Such as an intermediate layer or a lightweight rain jacket. Then you need the Agile 6. At the front are 2x 500 ml soft flasks and at the back there is a compartment for a water bag and a separate compartment for all the things you want to take with you. There is also a handy elastic at the back to which you can attach your poles.