Pallet racks provide organized storage for palletized loads or large containers to make use of vertical space and increase storage density in warehouses, distribution centers, and other storage facilities. They have vertical uprights that connect to horizontal beams to create multiple shelf levels. Loads are moved onto and off of the racks with forklifts or similar vehicles. Pallet rack kits include the necessary parts for building a pallet rack. Individual components such as uprights, beams, decking, crossbars, spacers, and hardware are used to expand, repair, or maintain existing racks. Enclosures and netting can be added to pallet racks to control access to their contents and stop loads from falling off them. Aisle guards and upright protectors help prevent damage to pallet racks from forklift collisions and similar hazards. Gravity-flow hangers and flow rack conveyors convert pallet racks into flow racks for first-in, first-out inventory initiatives.