The b!klimax AIR+ passive panel consists of a special gypsum board coated with a material that has a high light reflectance coefficient, capable of absorbing and reducing up to 70 per cent of the formaldehyde present in the ambient air. The surface, featuring square perforations, ensures high sound absorption performance whilst lending an original and elegant appearance. Thermal insulation is provided by a 40 mm thick layer of rock wool with a density of 165 kg/m³ (rock wool fire reaction class A1).