<br>This model motorcycle backpack Capacity: 37L. External dimensions:19"(H) x 11"(W) x 11"(D),waist belt MAX:55 Inch,chest belt MAX:60 Inch , it's a medium backpack; <br>Backpack is made of high density fabric-durable and water-resistant. <br>This model backpack molle system plus Seibertron sissy bar strap could fit sissy bar in most models of motorcycle perfectly. For more details of using, kindly refer to sixth and seventh photo on the side. (Seibertron sissy bar strap need to be purchased separately). This model backpack used double-stitched, Heavy duty zippers and utility-style cord pulls, Side and front load compression system, Comfortable padding back area, Ventilated mesh padding shoulder strap. <br>This model backpack has hydration compatible that works great for 2L Seibertron hydration bladder (backpack didn't include hydration bladder) fit for long time travel.