This is a waterproof fitted vinyl twin mattress protector in white, designed for a twin-size mattress measuring 39 inches in width and 75 inches in length. It features elastic for a secure fit and has a depth of 12 inches. The protector is hypoallergenic, dust mite proof, and easy to care for, making it ideal for kids and teens. It is part of the Lilith product line by Mainstays.