Bharat Marketing Is Leader Suppliers Gyptone Board / Quattro Boards We Are wholesalers in Bangalore. GYPROC GYPTONE BIG QUATTRO Boards These boards have square perforations punched in with great precision. The boards are backed with an acoustic tissue. Noise Reduction Coefficient (NRC): 0.6 (Without Glass wool) & upto 0.8 with Glasswool backing Perforation Area : 16% Reaction to fire: BS 476 Specification NOMINAL SIZE (MM) 1200 x 2400 x 12.5 WEIGHT (Kg/m2) 8.0