This pack is incredibly versatile - with the base pack being more than enough for day trips, but offering the compatibility of Vario Zip-Ons. The zip-ons allow you to customize your space from as little as 8 litres, and up to 45! With the ABS TwinBag system, the Vario pack offers a better bearing surface, snow flow dynamics, and stability. With ergonomically shaped shoulder pads and a padded hip belt, this pack will be comfortable from alpine start to apres! An excellent option for backcountry safety!