Not liquid proof. It only extends the lifespan of your mattress. Upper surface: 100% quilted COTTON fabric. Bottom surface: Interlining. Side surface: It is a tulle fitted sheet that completely covers the side. It has a soft and light texture. It does not stain and does not cause odor. It is ideal for people who have night sweating problems. It is useful for long-term hospitalized patients. For the correct result, you should measure your mattress and choose the size according to its exact dimensions. If your bed is 160x200, you should choose 160x200. Do not choose either too big or too small. Washing instructions: Do not use bleach or similar chemicals. Wash only with laundry detergent. It can be washed in the washing machine with plenty of water. Do not dry clean. Do not use bleach or bleach. Ironing should not be done. Do not put it in the dryer.