I purchased this single-size waterproof box sheet on Rakuten. It's new, unused, and compressed. Color: Beige Size: 100 x 200 x 30 cm Rakuten purchase price: 2880 yen 【Completely Waterproof】 The back side uses a highly breathable TPU waterproof membrane to enhance waterproofness, preventing moisture from sweat or water from reaching the mattress. It's perfect for nursing care, bedwetting, and effectively protects against water penetration and stains on futons and mattresses. Great for co-sleeping with children or sleeping with pets. The side portions are also waterproof, preventing water from seeping through.