When you're going to be out all day, you want to be prepared but don't want to be weighed down. The Gregory Z 25 Backpack's low weight and sleek design belies its substantial carrying capacity you can stuff 35 pounds worth of picnic in it without worries. It's a breeze literally in warm weather, thanks to the updated CrossFlo suspension system features a perforated frame sheet and a mesh back and shoulder straps to increase airflow. The high quality ripstop nylon combines durability and low weight speaking of weight, this model is 30% lighter than last year's version. The interior sleeve with a hydration port and side mesh bottle pockets store lots of water to keep you lubricated on long days in the woods reservoir not included.