Long Wearing Stay Soft Boilable Vinyl Standard Size 28" x 52" Waterproof Layer Protects Mattress, Wipes Clean With a Damp Cloth Fitted Cover Encases the whole mattress. Please measure Your Crib Mattress Before Purchasing Long Wearing Stay Soft Boilable Vinyl Standard Size 28" x 52" Fitted Vinyl waterproof- Keeps the babies mattress fresh Zippered Cover Encases the Entire mattress - keeps bugs and dirt out Waterproof Layer Protects Mattress, Wipes Clean With a Damp Cloth Please measure Your Crib Mattress Before Purchasing