The Sof Sole® Deodorizing Shoe Inserts provide an eco-friendly solution to help absorb tough odors. The inserts contain bamboo charcoal to absorb and filter odor, control moisture, and help prevent mold from developing to keep shoes fresh wear after wear. The product's design helps maintain the shape of your shoes. Our Deodorizing Shoe Inserts can be used as often as needed. They may be refreshed by placing them in the sun for at least an hour once per month.