Because rivets have wide grip ranges and are single item attachment parts, inventory cost savings are significant. Varying lengths of screws, grip range limitations on u-nuts, throat depths on u-nuts, washer and non-washer configuration of bolts, etc., all add up to large part inventories. Higher volumes of fewer parts, on the other hand, add up to dollars saved in not only piece part savings but in warehousing, labor, handling, and assembly line costs for stocking, purchasing, and so on. Effective Fastening of Dissimilar Materials: The controlled expansion of rivets provided uniform compression, which in turn, allows many types of dissimilar materials to be effectively joined. Metal to plastic, plastic to plastic, glass to metal, and paper to metal, are just a few of the possibilities. Various design features of some types of rivets allow for maximum load spreading for joining even the softest of material.