... 600*600,1220*2440,1220* Detailed Product Description: 1)Material:Mineral fibre board 2)Specification:600*600,1220*2440,1220*3000MM. 3)Thickness ... 7)Office, store, plaza 8)Hotel, restaurant, kitchen 9)Hospital Acoustic ability: 1)Perforated with SoundTex paper absorb modulus: NRC=0 ... .7 2)Acoustic level: plain : CAC=40dB perforated: CAC=24dB Fire proof ...