The Auralex QuadFusor Sound Diffusor (4 Pack) is designed to optimize the scattering of sound within a room. The polystyrene foam panel's shape is derived from four MiniFusors arranged in a 2' x 2' array. The diffusion of sound is helpful for managing room reflections and maintaining the sweet spot within your listening space. The panel can be painted with water-based paints and adhered to the wall or ceiling. This package contains 4 diffusers.