Of great aesthetic prestige, these cylinders belong to the family of expanded resin panels and are dedicated to correcting acoustic problems in open space rooms with large volumes and are particularly suitable for installation in high-rise rooms. The Cylindrical sound-absorbing elements are made in a single monolithic block of acoustic resin, by means of a double axis cutting machine which allows to obtain each required section. The particular method of installation suspended from the ceiling allows the elements to be placed in an intermediate position with respect to the free volumes of the rooms, interposing themselves with the trajectories of reflection of the sound waves between the various surfaces and producing a cut in the “sound tail” of the sounds, thus generating considerable benefits on the Reverberation Time. The panels in the Cilindri series have high sound absorption properties due to porosity, due to the physical alveolar structure of the expanded resin, with excellent performance even at low frequencies thanks to the high thickness of the material that makes up the elements.