A comfortable airflow foam-pad back design of this rucksack bag with soft, multi-panel breathable mesh padding unique shoulder strap provides maximum back support , helps relieve stress of your shoulders and keep you back dry in summer. Providing both ergonomic comfort and travel convenience. Good to serve as mens backpack for work , black waterproof rucksack for school, casual backpack, laptop rucksack,travel laptop bag, mens business backpack, smart travel backpack.POERMA waterproof backpack is made of water-repellent and tear-resistant 900D high density nylon & PU coating fabric with double-sided smooth zippers and reinforced stitching for lasting durability. It will serve you well as a large men's briefcase, professional office business work bag, business laptop backpack, travel backpack or large college backpack, high school rucksack. This laptop bag is good for trips, especially for business,camping & college student.