Systems and devices are provided for loading a transportation unit (150). The system includes a pallet rack unit (202). The pallet rack unit is configured to receive and support loaded pallets (102). The pallet rack unit is configured to be loaded into the transportation unit with other pallet rack units that are substantially identical to the pallet rack unit. The pallet rack unit and the other pallet rack units, together, substantially fill a length and a width of the transportation unit. The pallet rack unit includes a base configured to receive a first loaded pallet. The pallet rack unit is further configured to be forkliftable. The pallet rack unit includes a plurality of posts coupled to the base and at least one height adjustable shelf coupled to the posts. The at least one height adjustable shelf is configured to receive and support a second loaded pallet. Additional shelves may be used to handle additional loaded pallets.