The Phoenix Extreme 35L Backpack is the perfect medium sized bag for big adventures. Designed with ripstop polyester, with a waterproof rain cover included, the backpack is durable, hydro compatible and has multiple pockets for convenient storage. Rip Stop Fabric: Stop rips in their tracks with this heavy duty fabric. Hydration Compatible: A compartment specifically for a hydration pack. A hydration bladder is not included. Rain Cover: Found in a concealed pocket usually at the bottom, the rain cover folds out to protect your rucksack from the rain. Chest/Sternum Strap: Offers support for your back by helping to distribute weight and balance your pack. Security Pocket: Zipped pocket for your valuables. Lots Of Pockets: Multiple pockets to keep valuables safe.