Two of the three shelves move through positions 2.3 in apart, so a single narrow tower can hold paperbacks at one end of the year and box files at the other. The bay measures 15.5 x 11 in inside a frame 16.5 x 11.5 x 31.5 in - slim enough to stand beside a desk, a wardrobe or a doorway. The top surface takes 55 lbs and the shelves 66 lbs between them. Natural engineered wood and MDF bring the weight to 20 lbs. One bookcase and an instruction sheet ship per carton.