More babies sleep on a Sealy than any other brand, making Sealy the number-one crib mattress brand in the USA. The Sealy Baby Ultra Rest crib and toddler bed mattress is built extra-firm with 204 interwoven steel coils for firmness and lasting durability. Full perimeter border wire keeps the edges firm and weight distribution bars help prevent sagging. Double support and comfort layers all around provide a firm yet comfy sleeping surface. The entire cover is wet-proof and wipes clean with a damp cloth. This Sealy mattress fits both cribs and toddler bed frames.