Sound Balance acoustic tile, light grey, set of 2. Absorbs sound, optimising the acoustics in open-plan offices. Acoustic efficiency: sound absorption class B, sound absorption coefficient αw = 0.80 (sound absorption coefficient αw as determined by DIN EN ISO 11654), tested and certified by Müller-BBM, an independent institution for acoustic assessment. With original tesa® adhesive strips pre-mounted on the back, the tiles are mounted without drilling and can be removed and repositioned as required. A new set of adhesive strips (SB190) is required to reposition the tiles. Each tile is 400x400x42 mm in size.