A waterless cold-air diffuser for the big rooms in your home. Pillar turns pure essential oil into a dry, fine mist with air, not water and not heat, and carries it across an open living room of up to 1,500 sq ft. At about 10.5 in (27 cm) tall and 1.4 lb, a little shorter than a wine bottle, it sits on a side table, shelf or console like