This style of bag is called top load because they open only at the top; this is a common configuration in military gear bags were issued years ago. The flaps fold down over each other and a metal clip through an eyelet helps keep them closed. There is a single strap that you can use to throw this bag over your shoulder to haul it around. This is also a double-reinforced handle on the side. These bags are made from heavy weight canvas and are tough enough that you can throw them under a bus or drag them through an airport and not worry about the damage. Please note: the measurements are provided by the manufacturers and are apparently based on an empty bag laid flat. Actual size when the bag is filled and the tops folded down is less. Medium bag measures 21” x 36”. Large bag measures 25” x 42”. Extra Large bag measures 30” x 50”.