Push-back racking combines operation efficiency with high density storage. Front and back beams are connected by inclined rails with nested carts placed on top. When storing, pallets are placed on top of the front cart which will be pushed back by the next stored pallet exposing the next cart underneath. When extracting the outer pallet, the cart inside will automatically slide out due to gravity. Storage depth can be 2-4 pallets deep. Compared with selective racking, push-back racking increases storage space by 30%.