Pedag boot shapers are cleverly designed to keep your boots in shape. But they also expand to fit almost all boot widths. Make drying and cleaning your boots much easier. Gently smooth out wrinkles. Improve air circulation inside your boots. Make storing and hanging your boots easier. Made of plastic with a metal spring that expands and contracts for easy insertion and to fit your boot shaft width. These are boot shapers NOT boot stretchers, Pedag boot shapers are made for people who want to preserve their boots exactly as they are.