DreamFit Degree 1 Basic DreamClean 100% Cotton Terry Cloth Mattress Protector - King 100% cotton Body Vapor Breathable; Resists the Build-up of Allergens; Premium Terry Cloth; 100% Waterproof 10 Years Insured Protection Patented DreamFit Guaranteed to Fit Guaranteed to Stay On construction fits any sized mattress. Patented strap design guarantees your DreamFit fitted sheet will stay put even with the addition of feather beds, mattress toppers, or foam. High Performance Elastic sewn around entire sheet- 4X wider and 20X stronger than standard elastic.