This is a set including a 60x90cm mini mattress, a mattress cover, two waterproof covers, and a pillow. The covers, waterproof covers, and pillow have been disinfected and bleached with an enzymatic bleach, and then washed with a gentle detergent (Saraya Happy Elephant) that is mild for babies. The waterproof covers show some signs of use, but there are no stains. They are included as a bonus. Having multiple covers is convenient for changes.