It is not a liquid-proof mattress, it is a mattress protector. it provides protection against small liquids such as sweat, but it is not liquid-proof for larger amounts of liquids. upper surface: 100% cotton 57 wire ranfors fabricinner filling: 120gr/m2 1.quality fiber filling bottom surface :30gr /m2 interlining edge: cotton-polyester blended fabric our fully permeable undersheets with rubberized edges do not slip under the duvet cover and offer excellent protection without interrupting your comfort. for this reason, you should choose the same size product as your bed when ordering. if you do not want to use the product for many years and have no shrinkage problems, wash it at as low a temperature as possible. recommended maximum 40 degrees. it has been proven to extend its useful life. Improved version for clearer understanding and better search visibility. Suitable for users seeking detailed and reliable product information.