A shelf rack includes first and second identical shelf units each including a first frame with first and second legs having respective first and second feet, a second frame with third and fourth legs having respective third and fourth feet and at least one shelf. The second and fourth feet have an outer diameter that is less than an outer diameter of the first and third feet. The second shelf unit is inverted and the first and second frames of the first shelf unit toollessly assemble to the first and second frames, respectively, of the second shelf unit by mating the larger outer diameter feet of the first shelf unit with the smaller outer diameter feet of the second shelf unit and mating the larger outer diameter feet of the second shelf unit with the smaller outer diameter feet of the first shelf unit.