Facilitate block stacking on shelf. The narrow part of these shelf is open so the wheelbarrow enters in a tunnel. The first pallet remains on the ground and the other position rest on beams of shelf; this protects the packaging against damage caused by crowding. In the “drive in” system, the stacker is make back to front. To right and left there are other shelf in the same system, that allows the stored block without loss of space in corrodors.