Nothing can top your Marpac mattress—except this. It’s the perfect protection for your smart sleep investment. Smooth, high-tech surface puts a safeguarding layer between you and your mattress with breathable, 100% waterproof material that lets air through—but not spills. It's allergen- and dust mite-proof and the Universal Elastic Fit with 18-inch pockets is easy to put on and stays put but is specially engineered to let the luxurious feel of your Marpac mattress come through.