The box has been opened once for inspection, but the protector itself is unused. The size is double, but it worked fine on a semi-double mattress. I'm also open to price negotiations, so feel free to ask. Quoted from the website: 【Waterproof Function】 This Emma mattress protector is completely waterproof, protecting your mattress. It protects against bedwetting and spills, providing a clean sleep environment. 【Antibacterial Function】 It uses antibacterial material to prevent the growth of bacteria, allowing for safe use. It is especially suitable for babies and children. - Brand: Emma - Product Name: Mattress Protector Double - Functions: Waterproof and Antibacterial - Review Rating: 4.5 (998 reviews) - Packaging: Boxed - Price: ¥19,000