【100% Cotton】Side Mesh Breathable Waterproof Sheet Mamoru-kun Waterproof Box Sheet Single Size Machine Washable, Tumble Dryable, OK Anti-Dust Mite Sheet Bedwetting Sheet Mattress Cover Bed Cover (Single) I am selling this because I accidentally purchased it. * I only opened it once to check the contents, and it is unused. * Please refrain from purchasing if you are concerned about this not being a sealed product. The following is a product description from the sales site: Original Waterproof and Anti-Dust Mite Bedding Specialty Store [Shirokuma Care] We specialize in the development and sale of waterproof and anti-dust mite bedding. As experts in functional bedding, we are committed to providing "more safe and reliable products" and actively collaborate with third-party organizations in technology development and quality control. [Water Resistance] 17,110mm [Breathability] 45g/㎡・h [Dust Mite Passage Rate] 0% [Formaldehyde] 0.00ppm [Oeko-Tex Standard 100 Certified] ● [International Standard Certification Obtained] ISO9001 / ISO14001 / ISO18001 / BSCI Blocks allergens and house dust ● Prevents house dust and allergies with high-performance bedding ● Washable at home, machine washable, tumble dryable ● Extends the life of bedding. Breathable waterproof material Reduces stuffiness with breathable waterproof material! You can use it hygienically without staining your bedding. Surface: 100% cotton, Back: Waterproof and anti-dust mite processed polyurethane 100%) * Breathable polyurethane resin coating ● [Side mesh type] Lightweight and quick-drying Size: 100 x 200cm, Gusset 35cm Country of Manufacture: China (Japanese standards and management)