Dimensions: 52L x 27.5W x 5H in. Foam core mattress with removable/washable, water-resistant liner. Double knit polyester outer cover also removable/washable. White cover. Meets federal flammability standards. Foam breathable and contains no ozone depleters. Let all your worries drift away as your baby drifts into dreamland on the Westwood Design Imagio Classic Foam Crib Mattress. This mattress is made of self-expanding foam core for a firm and breathable cushion in your child's crib. The crib mattress has a water-resistant liner that can be removed and machine washed when needed. The double knit, polyester cover is soft against your infant's skin and can also be removed and thrown into the washing machine. The mattress meets all federal flammability standards and contains no ozone-depleting toxins.