Componibili. The Componibili is available in two diameters, 12.5″ and 16.5″. The 12.5″ diameter is available as either double tiered or triple tiered storage units. The 16.5″ diameter is a modular system. There are three pieces available, two separate storage units and a closure lid. The small single unit is just over 9″ and the large single unit is just over 15″. They will stack in any configuration, only one closure lid is necessary per tower.