magnesium oxide board Fireproof : Grade A Keep warm, insulate against heat, the sound insulation Moisture ... constructing. Especially the unique waterproof, fireproof , corrosion proof and plasticity are better than normally used wooden board, paper ... Fireproof : Grade A2) Keep warm, insulate against heat, the sound insulation3) Moisture resistant4) Construction simple, easy and swift, easy to decorate, ...