Shelf Bins are the economical longer-lasting replacements for cardboard bins. Plastic Shelf Bins are typically designed to nest inside one another when they are not in use.  Shelf Bins have a very economical price since they do not have the need to support the weight of a stacked bin above them, meaning less material is required to manufacture them. While cardboard bins typically wear out or stain, these plastic bins withstand constant use. Plastic shelf bins are available in several colors thus enabling color coding the product stored in them.  Plastic Bins are made of Polypropylene, a strong plastic material. Plastic shelf bins are widely used on mobile pick racks or stationary shelving units.  These nest inside of each other when empty.