This shoulder bag is made from heavy cotton duck canvas, trimmed in a light canvas, and complete with signature Steampunked Out leather details, including the bottom, strapping and buckle closures. Designed to work collaboratively with the map case, this bag can be worn with the map case slipped onto it as a unit or worn by itself. The shoulder strap comes with a buckle, for easy adjustment for wearing over one shoulder or across the chest. There is both an inner and outer pocket stitched onto the bag. The basic dimensions are: 13" wide, 10 1/2" height, 3 3/4" deep. There is plenty of room for a 3 ring binder and a small laptop or iPad.