DPM?s N Scale Modular System offers you unlimited building options. Interchangeable plastic wall sections make it fun and easy to create buildings of any size, shape or height. Assembles easily with plastic model cement or solvent. Build as many stories as you need: One-Story Building - Use street or dock level wall sections and cornice. Two-Story Building - Use street or dock level wall sections, top with one story wall sections and cornice. Three-Story Building - Use street or dock level wall sections, top with two story wall sections and cornice. More Stories - Add additional wall sections to create as many stories as desired. Wall/window packages include three identical double bay wall sections with pilasters, doors, windows and clear window material where needed. All wall sections are the same color and width (3 1/2").