Sized in short, regular and long, the First Ascent bags are mummy shaped with an outward slanting footbox which follows the natural line of your foot. The Standard 38" inside girth in the foot area is sufficient for most people. The Long bags are cut slightly wider from the knees up than the short and regular bags. The Broad fit bags are cut wider from hip to shoulder for the short and regular bags, and wider from foot to shoulder for the long version.