King Size Waterproof Mattress Pad Fitted Elastic Cover Protector - Stretches up 15" Inches KING SIZE MEASURES: 78" x 80" + 15" This mattress protector has a waterproof 100% premium layer, It will be your best protection to avoid nighttime accidents, liquids or stains. Mattress Protectors are super soft quilt made 80% bamboo and 20% polyester to promptly absorb any liquids. Breathable & Soft Surface Fabric: Made with100% polyester fabric and filling-in to support mattress pads that are soft and durable better than other materials. This mattress pad is machine washable. Machine wash cold on gentle cycle. Do not use bleach. Tumble dry on low heat. Do not Iron.