1. Compressed foam-designed for CD player and disks storage 2. Dual density foam-patented techonlogy which allows one surface to have rigidity and structure and the reverse surface various degrees of softness for cushioning 3. Compressed strap: keeps pack in place on user's shoulders stabilizing the load 4. Aero-spacer: unique three layer knit material that has built in air cells providing air circulation which ventilates and cools the body 5. Water proof: material used has water resistance 6. Y shape airflow backpack panel: provids comfort and air circulation 7. Size: 51 x 33 x 13.5cm 8. Material: polyester, nylon