Tropicfeel makes backpacks a bit differently. These are versatile and adaptable backpacks, each of which forms the core of what they call an "ecosystem" of specially designed accessories. Take this Shell backpack, which can reduce to an elegant 20 -liter backpack or expand it up to 42 liters for a weekend getaway. A special genius is 6 -liter "kangaroo" pocket that unfolds from the bottom and adapts perfectly to your muddy running shoes. Outdose and comfortable resistant with belts for the waist and sternum, it is elegant enough for the city and resistant enough for the mountain. The multiple pockets will help you maintain your organized equipment and you can access the main compartment through a upper flap or a complete opening. However, the really intelligent shell is the range of independent accessories that you can combine with it. The internal mod of 'cabinet', for example, provides storage of removable clothes and hung with integrated compression to help you wear 20 % more things