Back pack Author Twister, anatomic design of back construction and shoulder straps with mobile phone pocket. Air Vent System for perfect ventilation. Main and chest belts, reflexive stripes for better safety. Many inner and outer pockets, inner fixation for big water bottle. Special fixation of helmet, pump and flashing light. Separate pocket for H2O bag. Mobile phone holder integrated into shoulder belt, volume 21 l, weight 780g.