Physician designed for babies' wellness, the LifeNest naturally maintains babies in a comfortable back sleeping position. The supportive inclined netting, allows babies to breathe through if they flip over. The hammock part provides a curved surface that cuddles babies. The hypoallergenic netting is dust mites free. LifeNest sleeping System comes with a white fitted coversheet. LifeNest bag shaped Coversheets are closed by a zipper for your baby's safety and machine washable for easy maintenance. Extra cover sheets, white and colored are sold separately to compliment your nursery.