A last is essentially a three-dimensional model or mold that a shoe is built on that mimics the shape of a typical human foot. Every shoe manufacturer uses several different lasts to make shoes with different characteristics: width in the heel, midfoot, and toe box; overall volume; toe profile; etc. Some climbers find that one particular manufacturer uses last designs that fit their feet better than others. However, since every last is different, most people still need to try on any new model to ensure it has a similar fit to a known model in a manufacturer's lineup.