Auction for ONE PIECE 800mm X 450MM (over 1.75 kg)Shinning chrome aluminum surfaceProduct Description:The upper layer, immediately opposite the noise source, is a layer of semi-open cell dense acoustic foam which provides a low-reflection surface. This upper layer of foam provides some sound attenuation, expecially of higher-frequency sound . The butyl rubber layer at the base of the 3-layer material is directly attached to the substrate. This layer acts as both an acoustic barrier (effectively attenuating the transmission of sound energy through the material) and as a damping layer, reducing vibration in the substrate. The Aluminium layer just hold the construction/Butyl Rubber layer — 2 mmAcoustic Foam Layer — 8 mmAluminium layer — 1 mm
