The vango traverse 40 is a 40 litre rucksack with back ventilation to provide comfort and stability the air vent back system keeps the rucksack away from your back increasing airflow between you and the bag the traverse features a detachable rain cover in the base of the pack to help protect the bag in wet weather while also aiding visibility in low light the bag also features hydration compatibility allowing it to be used with water reservoirs for easy and convenient hydration on the move