Outer layer is made of super soft and environmental PE membrane, free from acid and alkaline. Compared to traditional plastic membrane, PE membrane is far more softer and comfortable. Also it is hydrophilic but no leakage. Inner layer is made by weaving spun silk into unique net-form membrane. It is a silly, smooth membrane with countless meshes which makes the functional ingredients evenly distributed so that they are easy for the skin to absorb. Soft and water proof material, fit your foot well. It will provide moisture and nutrients to your dry skin. Foot Mask is specially formulated to soften the callus and to moisturize feet. The main ingredients such as papain are helpful to remove the callus.