Durable Steel Coils Made In Usa: Extra-firm crib mattress core with 150 American-made steel coils delivers reliable posture support, long-lasting durability, and consistent firmness for infant and toddler sleep through years of daily nursery use Edge To Edge Firmness: Reinforced edge-to-edge crib mattress design with EverEdge steel guards adds stability like an adult mattress, reduces sagging, improves safety, and helps toddlers climb in and out with confidence Firmer Infant Side: Firm infant crib mattress side features hypoallergenic cushioning engineered for newborn safety, offering proper firmness to support developing heads, necks, and spines while meeting recommended infant sleep standards Softer Supportive Toddler Side: Dual sided crib mattress includes a softer toddler mattress side with extra comfort layers, creating a cozy yet supportive surface ideal for growing children, side sleepers, and extended crib use Breathable Waterproof Cover: Waterproof crib mattress cover wipes clean easily, resists tearing or unraveling, and includes a breathable airflow pocket to promote ventilation, temperature regulation, and a drier, more comfortable sleep environment