Plush and Airy: 100% Jersey Cotton Ely's & Co.'s Crib / Toddler Bed Sets are created from lightweight, plush and breathable fabric. Composed of 100% high quality Jersey knit cotton, our Crib sheets offer cozy, welcoming environment for babies to rest their weary heads as they drift off into nourishing slumber. Adjustable Elasticity:Fits Multiple Mattress Sizes Ely's & Co's specially designed crib sheet set includes flexible, stretchable elastic, enabling a great fit and tight seal on all standard mattresses sold for Cribs and Toddler Beds.