This double sided two in one mattress grows with your child. Our 182 heavy duty 15.5 gauge steels coils and 9 gauge border rods provide maximum durability and support to baby's developing spine. (The lower the gauge the thicker the steel.) Flex Edge Clips for the ultimate in side edge support and safety when baby starts to pull themselves up to a standing position or when the mattress is used with a toddler bed.Cotton-poly coil wrap prevents loss of cushioning material. Two layers of Ortho-Insulator pad for additional durability. Blended cotton provides a firm supportive sleep surface to baby while the toddler side offers CertiPUR-US certified convoluted foam for additional comfort. The deluxe Jacquard fabric cover in our Fleur De Lis pattern is not only beautiful but practical as well because of the dust mite barrier, is hypo-allergenic and has a waterproof back.Air-vents promote mattress freshness. Cloth binding is sewn with a lock stitch that helps prevent edge seam from splitting and moisture from entering.Proudly made in the U.S.A. from domestic and imported sources.