A 4-tier bookshelf cut from solid rubber wood and built just 14 in wide, so it slips into the gap a standard bookcase cannot use. The shelf gaps alternate between 12.5 in for hardcovers, binders, and a potted plant and 5.5 in for paperbacks, CDs, and stacked mail. Reinforced wood guardrails run up both sides of each tier, catching items before they slide off a 13-in deep deck. Every shelf carries up to 11 lbs, the 23-lb frame goes together quickly with the supplied hardware, and two anti-toppling kits fasten it to the wall for a living room, study, or kitchen.