ROCKMAX mgo board, also call magnesium sulfate board. it is made from nature minerals including: magnesium oxide powder, magnesium sulfate, perlite, reinforced by plant fiber and glass mesh fiber. ROCKMAX use newest chloride free technology to produce 100% noncorrosive fireproof board for steel frame partition. It is class A fireproof, moisture proof, impact resistant, low heat conduction, highly recommend for interior fireproof partition board and ceiling. For more details: https://www.rockmaxboard.com/mgo-board/