Floor systems often feature boxes, bins or totes rolling on simple plastic or metal skate wheels, ball transfers or free rollers. Items are loaded then sent down a run of roller conveyor, manually or by gravity. Systems often feature separate runs of conveyor, angled to feed in the opposite direction, for return of empties.
These systems are typically suitable for lighter parts and bins. Larger or heavier parts or racks, that roll downhill, collect momentum and may pose a safety hazard on the receiving end.