If you're looking for all the benefits of our ultrasonically welded seams with the economy of our Premium model, the Sopora Premium Plus was developed for you. It is everything you need in a mattress without compromising quality. The Premium Plus is a 5" deep, all foam mattress with dual sleep surfaces. Made with CertiPUR-US® certified, and GreenGuard® Children and Schools certified foam. The Premium Plus is engineered to withstand wear and provide even ergonomic support. As your child develops, the density required of their sleep surface can change. Which is why we offer dual sleep surfaces. One side is made of eco-friendly, ultra firm, high-density foam. Eco-Friendly foam was developed by industry leaders, to deliver cleaner foam. Eco-Friendly foam products utilize a blend of natural oil based and conventional polyols. Natural polyol is made from natural plant based renewable oils. This blend enables Eco-Friendly foam to perform as well as conventional foam without sacrificing comfort and helping the environment at the same time. The other side of the mattress offers Eco-Friendly high-density foam which is plush in feel and luxurious. The Premium Plus offers BabySafe side seams, which are welded with ultra-sonic sound waves to keep wetness out, allowing the inside of the mattress to stay clean. BabySafe seams are dropped to the sides of the mattress creating a seamless waterproof edge with no decorative cording or holes on the surface. This eliminates entry points for allergens, bed bugs and fluid leakage. The Premium Plus offers square corners and edges to fit tightly into the crib, with no rounded corners or surface designs that can trap dirt or dust mites. The rectangular shape of the mattress, the same shape as the crib, holds sheets tight to keep baby safe. The Premium Plus' medical grade, stretch knit mattress cover is compliant with all current safety standards. Its lightweight and pliable nature enables the baby's body to conform to the surface while allowing the inner construction to provide comfort and ergonomic support for which it was designed. The cover is vinyl, PVC, lead and phthalates free. It cleans easily with a damp sponge and won't retain unpleasant odors or stains.