the db hugger 30l is a smart and roomy travel-backpack - approved as cabin luggage. the hugger 30l from db combines everything and more that you would expect from an optimal travel backpack. approved as hand luggage, this backpack will follow you from the airport to the mountain peaks of the himalayas.rib cage constructionâ„¢inspired by the human rib cage, which protects the body's most valuable organs, db's patented rib cage constructionâ„¢ protects your gear in the bag. the rib cage construction is built from strong, lightweight abs ribs formed as a triple-fold structure. this means that conventional padding can be dispensed with. this makes the bag lighter and yet protected all around.