Moisture-Absorbing Sensor Futon Dehumidifying Sheet & Sheet This dehumidifying sheet protects your bed and futon, which you use every day, from mold, dust mites, etc. Place it under your futon or mattress pad, and the sheet will absorb moisture from your futon. Plus, the sensor will let you know when it has absorbed enough moisture! Size (approx.): 90 x 180 (cm) How to use: For futons: Place the dehumidifying sheet on the surface that is in contact with the tatami mat or flooring. For beds: If you sleep directly on the mattress, place the dehumidifying sheet between the mattress and the bed. If you use a mattress pad, place the dehumidifying sheet under the mattress pad. Material: Surface fabric: 100% polypropylene Back fabric: 100% polypropylene Inner material: EVA resin (with silica gel B type) Due to shipping costs, we will fold it in two for shipping. Thank you for your understanding.