The roll top closure and the three dimensional shape are the key features of a messenger backpack. It makes it easy to stow and remove things out quickly. Tough nylon material with tarpaulin liner, making the bag a heavy duty structure. The two belt straps on the front could even hold a bicycle wheel. - The two side pockets feature a mesh bottom for drainage. - Large flap closure pocket on the front side. - Quick accessible flap zip pocket. - Organizer pocket inside the front pocket. - laptop pocket on the back of the main compartment. - Shoulder straps with an S-shaped contour that fit snugly along the body. Urethane foam padding is incorporated into the back and shoulder areas to absorb weight. - Features a chest strap to distribute weight and provide a comfortable carrying experience. - A huge capacity of 35L - 50L. - A very useful bag for carrying bike frames & wheels, race days, traveling, etc. *Should be an acceptable size for carry-on at the airport, but we highly recommend checking with the airline company.