Model (I) features a full-width utility cabinet with one fixed shelf and center divider while model (J) has (8) 18"Wx12"Dx3"H adjustable compartment boxes and a half-width cabinet with 2 adjustable shelves. Both cabinets offer key locking security and rest on top of (40) 4"Wx11 7/8"Dx4 1/2"H compartments. All-welded cold rolled steel construction. Gray baked enamel finish. Ships unassembled.